Give your work truck a classic, high-visibility look with the Weather Guard 121-0-04" bright aluminum diamond plate. Its clear ARMOR TUF powder coat lets the raw diamond plate shine through while sealing the aluminum against corrosion, fading and road salt. If you want the traditional, high-visibility look most buyers picture on a work truck, bright aluminum is the go-to choice. Scratches and swirl marks also tend to blend into the diamond plate instead of standing out. This full-size, low-profile aluminum saddle box straddles the top bed rails behind the cab and keeps a lower lid line for better rear visibility, with 11.0ft³ of secured, weather-sealed storage. A five-piece welded aluminum diamond-plate body with a reinforced C-channel front keeps it strong yet light, and a full-perimeter D-shaped weather seal locks out rain and dust.
What's Included:
121 Series full-size low-profile aluminum crossover (saddle) tool box in bright aluminum
1Key UltraLock push-button locks, keyed alike
Under-rail mounting clamps and hardware for a no-drill install
Welded Aluminum Diamond-Plate Build A five-piece welded aluminum diamond-plate body with a reinforced C-channel front panel keeps this box strong yet light. It resists jobsite abuse and road salt without adding the weight of a steel box. This one is finished in clear ARMOR TUF powder coat over bright aluminum diamond plate.
Bright Aluminum Clear ARMOR TUF Finish A clear ARMOR TUF powder coat protects the raw aluminum diamond plate while keeping that bright, traditional work-truck look. It resists corrosion, road salt and fading without hiding the diamond-plate texture.
1Key UltraLock Security Tamper-resistant push-button locks sit recessed when locked, giving a quick visual cue your gear is secured. The 1Key UltraLock system lets you code multiple boxes on a truck, or a whole fleet, to a single key.
Full-Perimeter Weather Seal A memory-resistant D-shaped, multi-ridge weather strip runs the entire lid perimeter to keep rain, dust and debris off your tools, so your gear stays dry and ready in any weather.
Reinforced Lid With Gas Struts Gas struts hold the reinforced lid open near 90 degrees for easy one-handed access, and welded strut shields protect them from damage. The steel-reinforced lid resists flex and stands up to daily use.
Saddle Fit Across The Bed The box straddles the top bed rails behind the cab, keeping your bed floor open for sheet goods and cargo. Enhanced tie-down buckles and 12V PowerSync-ready access round out a box built for working trucks.
Reinforced Body, Automotive-Grade Hardware Weather Guard specifies a five-piece welded body for the 121-0-04, with a C-channel reinforced front panel and a heavy-duty C-channel reinforced lid, so the box stays square when it is loaded and when someone stands on the lid. The latch is an automotive dual-stage rotary mechanism, the same style a truck door uses, so it pulls the lid down onto the seal instead of relying on a friction catch. A welded gas strut shield keeps loose tools from knocking the strut mount out of line. The D-shaped ribbed weather strip is memory resistant, so it springs back after years of closing rather than taking a set and letting water track in.
Fit guidance: Crossover, or saddle, boxes mount across the truck bed on top of the two bed rails just behind the cab, so the box straddles the bed and leaves the bed floor open. At about 72" wide this size fits standard-width full-size pickups, and because it sits on the rails rather than the bed floor it works with short, standard and long beds on those trucks. Always measure your bed rail width and check clearance behind the cab before ordering. It is not designed for compact or mid-size trucks.
Type: Saddle mount across the top bed rails, clamp-in with no drilling · Time: About 20 to 30 minutes · Tools: Socket or wrench set and a tape measure; no drill needed with the included under-rail clamps · Difficulty: Easy, best done with two people for the lift
Set the box across the two bed rails behind the cab and center it left to right. Hook the included clamps under each bed rail and tighten the hardware evenly so the box sits flat and the lid seals all the way around. Because the box is wide, have a second person help lift and hold it while you clamp it down. Follow the Weather Guard installation instructions for exact clamp placement and torque.
Watch the installation walkthrough:
Resources
Everything you need for your Weather Guard 121 Aluminum Crossover Truck Tool Box, Full-Size Low-Profile, Bright Aluminum, in one place.
Warranty. Limited Lifetime Warranty from Weather Guard against defects in materials and workmanship.
Free shipping. This item ships free to the lower 48 states. Because it is an oversized item, it ships by freight and typically arrives in 3 to 7 business days.
Inspect on delivery. Please inspect the packaging before signing. If you see any damage, note it on the delivery receipt and contact us right away, and we will make it right.
Returns. Unused items in their original packaging can be returned within 30 days of delivery. If an item arrives damaged, defective or wrong, return shipping is on us. See our Returns & Refunds Policy, or email support@prestigetruck.com with any question.
About Weather Guard
Weather Guard has built professional-grade truck and van storage in the USA for decades and is the storage brand tradespeople, contractors, and fleets reach for first. Its steel and aluminum tool boxes, ladder racks, and van-interior systems are engineered to survive daily jobsite abuse and keep expensive tools secure and organized.
Known for weather-tight seals, patented locking systems, and heavy-gauge construction, Weather Guard products mount cleanly on work trucks and vans and stand up to years of hard use. The lineup spans crossover, low-side, and saddle truck boxes, ladder and van racks, drawer units, and fuel and utility tanks, so an entire work vehicle can be outfitted from one brand.
Backed by a strong manufacturer warranty and US-based support, Weather Guard is the name pros trust to protect the tools their livelihood depends on.
Authorized Weather Guard dealer. Prestige Truck is an authorized dealer of Weather Guard, so every tool box, rack and storage product you buy is 100% genuine and factory-new, covered by the full Weather Guard manufacturer warranty, and backed by our own US-based support team.
Weather Guard's official hardware video zooms in on the clamp and bolt kit that secures its truck boxes to the bed rails without drilling. It is a helpful close-up companion to the full box install and shows how the mounting brackets hook under the rail lip and tighten down. Use it alongside the printed instructions that ship with the box.
How the 1Key UltraLock System Works
A step-by-step look from Weather Guard at what the 1Key UltraLock actually does: how the cylinder accepts a new code, why the red push button retracts when the box is locked, and how the latch pulls the lid down against the seal. Worth two minutes before you set the box up.
How to Code Your 1Key UltraLock Lock
Weather Guard's official walkthrough for coding the lock so this box opens with the same key as the rest of your Weather Guard boxes. Follow it once when the box arrives and you can stop carrying a separate key for every lid on the truck.
Weather Guard's official hardware video zooms in on the clamp and bolt kit that secures its truck boxes to the bed rails without drilling. It is a helpful close-up companion to the full box install and shows how the mounting brackets hook under the rail lip and tighten down. Use it alongside the printed instructions that ship with the box.
How the 1Key UltraLock System Works
A step-by-step look from Weather Guard at what the 1Key UltraLock actually does: how the cylinder accepts a new code, why the red push button retracts when the box is locked, and how the latch pulls the lid down against the seal. Worth two minutes before you set the box up.
How to Code Your 1Key UltraLock Lock
Weather Guard's official walkthrough for coding the lock so this box opens with the same key as the rest of your Weather Guard boxes. Follow it once when the box arrives and you can stop carrying a separate key for every lid on the truck.
Frequently Asked Questions
Straight answers on specs, fit and support
Will the 121-0-04 fit my truck?
It is a full-size low-profile crossover, or saddle, box that mounts across the top bed rails behind the cab, so it fits full-size pickups such as the F-150, Silverado and Sierra 1500 through 3500, Ram 1500 through 3500, Tundra and Titan. It needs about 72" of rail-to-rail width. Measure your bed rails and check clearance behind the cab first, and note it is not designed for compact or mid-size trucks.
Does it require drilling to install?
No. The box ships with under-rail clamps and hardware, so it mounts without drilling into your truck. Most installs take about 20 to 30 minutes and go easiest with two people to lift and hold the box while you clamp it down.
How secure is this Weather Guard box?
It uses the Weather Guard 1Key UltraLock system with tamper-resistant push-button locks that sit recessed when locked, so you get a quick visual cue your gear is secured. The 1Key design also lets you code multiple boxes on a truck or a whole fleet to a single key.
How does the bright aluminum hold up outdoors?
Very well. The aluminum body will not rust like steel, and the clear ARMOR TUF coating plus the full-perimeter D-shaped weather seal keep water, salt and dust out while protecting the finish. A rinse and a wipe keep the diamond plate bright.
Does the clear aluminum finish need much upkeep?
Not really. The clear ARMOR TUF powder coat seals the aluminum, so it will not rust like bare steel and it wipes clean with mild soap and water. The bright diamond plate hides light scuffs well and keeps its look with basic care.
What is it made of and how big is it?
It is built from welded aluminum diamond plate with a clear ARMOR TUF powder coat over bright aluminum diamond plate. The exterior measures 72"L x 20"W x 18"H with 11.0ft³ of storage, and it ships at about 81.5 lb, so it is strong yet lighter than a comparable steel box.
What our customers say
4.8 · 144 reviews
5★1174★243★22★11★0
Photos from owners
+4
Nate
Verified
08/22/2026
Way better than by backseat floor board!
Convenient storage
Garrett
Verified
08/20/2026
Waited a long time...
I have waited years before buying a quality toolbox. Difference is amazing, wish I would have spent the money a long time ago. Ended up buying two so I could have one in both work trucks.
Clrcut
Verified
08/19/2026
Best box ever
Well built box. Excellent fit
Scott
Verified
07/07/2026
Superb box!
Went to TC to purchase a truck box. So many models out there in the 400+ range, but this one's reputation and quality was obvious. Well built, perfect powder coating and looks awesome on my 3/4 ton truck.
WAYNE
04/23/2026
Excellent box, well worth the price!...
Excellent box, well worth the price!
HomeDepotCustomer
Verified
06/27/2026
One of the best truck boxes . Great locking mechanism.
James BC
Verified
01/26/2026
What can I say, #1 it's a Weather Guard.
Weather Guard is the best box out there. This light gray box fits and looks great on my truck. The locking system opens on each side. Actually, my truck is a GMC AT4 metallic gray with the red hooks on the front. So you know this Weather Guard saddle box looks great.
James
Verified
10/21/2025
The entire process was trouble free....
The entire process was trouble free.
RonM
06/23/2025
Initial Review
Product arrived damage free. Finishes were as expected. The install could be better due to the tie down thread difficulty. The include tray has 4 slots for dividers, only 3 dividers included. Tray has pads on it that facilitate it sliding back & forth while driving which is annoying & damaging.
TOM
Verified
09/02/2025
Tool box came quickly. It was packaged well, and fit like it should.
B2Garcia
08/10/2024
Happy Happy Happy!!!
This truck box is awesome and the glossy black powder coat finish is top of the line! Fit perfect on my 14' F150 King Ranch, easy install took about 30 minutes all hardware was included! The dual gas shocks inside help pop the lid open a full 90°, comes with 2 keys, a sliding tray and 2 hooks to hold a 4' level. Very sturdy for an aluminum box. All my stuff fit very well, It's definitely worth the money! I get nothing but good compliments over it!
J South
Verified
07/28/2025
Weather Guard toolbox
Very well made, a quality product. The textured black matte finish matches the spray in liner in my truck.
Eric
Verified
05/11/2025
Great toolbox
I've had this box almost a month and use it often. It locks and unlocks easily, opens and closes easily, and has plenty of room. The tie down on the back of the box allows me to secure my pack-out boxes for secure transport.
Robeert
Verified
05/08/2025
Nice box, heavy duty....
Nice box, heavy duty.
Nb
Verified
04/26/2025
Great product would purchase again
Great product would purchase again
Frogdog1947
07/08/2024
Weather guard
This is a great looking box and I love it functions, my opinion is that it the best tuck Box in the world and it rate as a(5) star.
HomeDepotCustomer
Verified
04/19/2025
Box was actually gloss black not matte. But the gloss...
Box was actually gloss black not matte. But the gloss is what the weather guard product number indicated. Great box!
Ihook716
10/01/2025
Doesn’t latch
I recently bought this low profile box. I opted to spend the extra money and get the best quality box. Unfortunately I can’t get it to close and latch properly unless I get in the bed and put all my weight on it. I have yet to find a way to adjust this. It also came with a small dent on the front face. Please help
JohnnieD
Verified
01/18/2025
Looks and works great!
Bought this box a few weeks ago and it looks and works great! Quality construction and simple to install.
tganglin
Verified
12/26/2024
Awesome
Fantastic tool box!
Hoss
Verified
09/07/2024
Truck tool box for F250
Great assistance and help
Anonymous
07/14/2026
Matt Black Toolbox
My husband absolutely loves it. He loves the way it appears, locks, is sturdy, and extremely well built.
MjMof
Verified
09/04/2024
Weather guard toolbox--amazing!
I recently purchased this toolbox to have a more secure and tougher box for my tools, and all I can say is wow. Best tool box hands down I've seen/purchased. Extremely pleased with weather guard and their product! Would highly recommend this box. Pricey, but you get what you pay for and these are built to last.
Hoofing4P2
Verified
07/14/2024
Tool box
Great box for my F150
Roger
Verified
06/02/2024
Good Solid Toolbox
Solid toolbox best that i have had.
LEWIS
Verified
04/17/2024
Fit fine. Great quality
JEFF T
05/28/2026
There's a reason I buy Weather Guard
This is my third Weather Guard toolbox and I can say without a doubt they just keep getting better and better. The construction, the finish, and the locks are the best yet. But the real reason I buy Weather Guard is the phenomenal service I count on and received from Susan in customer care. I called last Thursday with a concern about the anchor points and label on my box, and today (Tuesday) I came home to this package waiting for me just as promised. She was knowledgeable, professional, pleasant and resolved my concern completely and quickly. There's a reason I buy Weather Guard - and her name is Susan. Thank you.
BobG
Verified
01/25/2024
Nice truck box
Great truck box. I can fit a ton of stuff in it. Looks good too!
Consumer 1000pp
Verified
05/16/2026
Weather or not
Price point is definitely of premium quality. Box is not poorly made but at that price I expect more
Kevin57
11/13/2024
Poor quality for the price paid
I bought this toolbox 2 weeks ago. Have opened and closed the box maybe a dozen times. The sheet metal screws holding the latch on the lid all came loose and fell off! I would think for the amount I paid for this product , I would expect a higher level of quality. This is not the first weatherguard I have owned and have always been very satisfied with the quality. It’s sad I had to repair this box after only owning it for 2 weeks. I will add photos of my repairs . I feel this should have been done from the manufacturer, or something more than sheet metal screws.
HomeDepotCustomer
Verified
03/28/2026
Good toolbox, but not as well made as they used...
Good toolbox, but not as well made as they used to be. Thinner metal, no dividers for tray, no rubber piece to put between the toolbox and bedrails.
Anonymous Hippopotamus
Verified
02/28/2026
Weather Guard toolbox
The locks are different. Not properly functioning when purchased. Not bad, just not Weather Guard standard that I’m used to.
Anonymous
08/13/2025
Weather Guard
Worth the extra money compared to cheaper truck boxes!!
DANIEL
Verified
02/28/2024
Would have given a 5 star but, the driver side lock had to be replaced. Great box other than that. Sturdy
C Booher
Verified
08/28/2026
Awesome!!!
Love this toolbox, compliments on it everywhere i go
HomeDepotCustomer
Verified
07/10/2025
Perfect tool box and great size for my truck
Perfect tool box and great size for my truck
Rzr
Verified
06/09/2025
Easy to install. Fits and looks great. Built strong enough to keep everything secure. Ship
Easy to install. Fits and looks great. Built strong enough to keep everything secure. Shipping was fast and no damage.
Dko3030
03/05/2026
Quality control, new locks, Huge key...
The first box i got was hot garbage. Horrible welds, not square at all, lid not centered terrible. I returned and got another and its fine. I'm not a fan of the new locks, they dont stay recessed when they are locked like they used to. Wish i had locks the old style locks and the new key is huge. It is by far the largest key on my ring.
Jman
Verified
08/16/2026
Tool box
Love this tool box. Very well built
HomeDepotCustomer
Verified
11/10/2024
Easy to install and top-quality manufacturing, Thicker gauge metal is superior to other br
Easy to install and top-quality manufacturing, Thicker gauge metal is superior to other brands I looked at. I considered lower quality brand to save money and so glad that I chose Weather Guard brand! It operates perfectly and we have had 4 major rain/wind storms and not a sign of moisture/dust on the interior. Locks on both sides and can unlock with just using one side, nice feature. Shipped to store and was in perfect condition, Excellent protection and palletized perfectly to avoid damages.
chas24
Verified
08/12/2026
Truck box
Truck box. Is great. Just had a little issue with it not opening from one side because the rod that worked the latch was too short. I fixed it myself and it works great now
B fuller
Verified
08/04/2026
Weatherguard
Fits well on 2500 ram truck
Dhoff
12/16/2025
Great tool box
I have owned 6 weather gaurd boxes over the years, the quality is always great. Sure they are expensive but you get what you pay for. Everything else is a cheap toy that constantly has issues. I don’t get paid to screw with my tool box all day. Pay the money and it hurts for a day, get a cheap toy and pay every day!
RW fisher
Verified
07/31/2026
Sharp toolbox , heavy duty / with nice features
Great toolbox with nice space
Water Tech
Verified
07/30/2026
Excellent
Sturdy, closes tight and locks easily. This is the best box and worth every penny.
Jason
Verified
07/19/2026
Perfect
Perfect fit. Perfect space. Super easy to install. Very happy.
Jose
Verified
07/13/2026
Toolbox for work
Also, experience employees are excellent with service
Joel
06/10/2024
Damaged
Product came damaged, otherwise no issues. Not a fan of the new locks. Feel cheap
DANMAN
05/31/2026
Low pro saddle box
Had high hopes for this box and while it isn't terrible, not quite what I expected. For the price point I was expecting a box built like a tank, and this one isn't. Saw other reviewers talk about the welds and, the welds on my box are decent but not spectactular. The lid on the box is different than most, not simetrical, kind of a weird gap in the back, not astheticaly pleasing. Have to set the locks with the key on first use which was unusual. Locks seems to be okay, not the smoothest operating. Release button on driver side seems to be a little glitchy, sometimes works good and other times hesitates, passenger side works fine. The keys are HUGE also, as long as the key fob for my ram and just about as wide. Don't really see the need for the key to be that large when it only inserts in the lock about 1". Thought the box was supposed to have the easy close feature but mine still has to…
Aaron J
04/09/2026
Changed locking mechanism
I bought this box today, I hope it lasts as long as my last one. I bought a dual lid in 2011 and has been awesome, the locking mechanism was what drew me to the product. I'm highly disappointed that Weather Guard changed there lock system. I really hopeful that the new system performs as a deterant like the old system.
Work every day
02/11/2026
It works
Good box not great if you’re looking for old school weather guard this isn’t it but works well just miss old style and quality
steve
09/12/2025
Great tool box
I chose this Weatherguard tool box for the low profile and storage, it is weather tight and great, knocked off a star because the stickers were all of center on the box
Rob
12/16/2024
Weather guard truck box
Solid box with excellent latches and locks. Struts are strong. Always have problems with other top box struts getting weak. I will see if these hold up, but if they don’t, lifetime warranty! One thing i don’t like, the box lid is difficult to get patched. I have to close the lid and then push with a fair amount of pressure to get it to latch and then the other side doesn’t completely latch. Hoping the seal will lighten up over time.
RANDY
08/06/2024
Mounting
The tool box is excellent in quality and craftsmanship. It is just what I wanted. The issue that I had was with the mounting hardware though. The clips did not adequately fit the bed on my GMC