How we made this guide: picks and specs come from our catalog and fitment data, owner quotes come from verified reviews and the guide was drafted with AI help, then checked and edited by Trevor Hall.
A low profile tool box sits lower above the bed rails than a standard box, and for a full-size truck the best low profile tool box is the Weather Guard 121 aluminum crossover, from $1,340. It is listed as a full-size low-profile box, 72 inches long with 11.0 cubic feet of storage, and its 144 owner reviews on file average 4.8.
For a mid-size truck the pick is the 131 crossover, from $1,333. Steel buyers take the 120, from $1,343. The 178 (from $1,161) and the 180 (from $989) are Low Profile Lo-Side boxes that sit on one bed rail instead of crossing the bed. The UnderCover SwingCase, from $219.99, is a swing-out case that mounts in the gap between the rear wheel well and the tailgate. The Weather Guard low profile boxes in our range run from $989 to $1,343.
What low profile means on a truck tool box
Low profile is the name for a box that sits lower above the bed rails than a standard box. Weather Guard sells both styles: the 121 has a standard twin in the 127 and the 178 one in the 174.
The listings give each twin the same outside size and capacity. The 121 and the 127 are both 72 by 20 by 18 inches with 11.0 cubic feet. The 178 and the 174 are both about 56 by 17 by 13 inches with 4.0 cubic feet. The listings give the twins the same numbers, though one 127 owner says the standard box holds more than the low profile model.
| Box | Style | Outside size (L x W x H) | Capacity | Material | Drain | Warranty | From |
|---|---|---|---|---|---|---|---|
| Weather Guard 121 | Full-size low-profile crossover | 72 x 20 x 18 in | 11.0 cu ft | Aluminum | None listed | Lifetime limited | $1,340 |
| Weather Guard 127 | Full-size standard crossover | 72 x 20 x 18 in | 11.0 cu ft | 15-gauge aluminum | None listed | Lifetime limited | $1,340 |
| Weather Guard 120 | Full-size low-profile steel crossover | 72 x 20 x 18 in | 11.0 cu ft | Formed steel | None listed | Lifetime limited | $1,343 |
| Weather Guard 131 | Mid-size low-profile crossover | 62 x 20 x 18 in | 8.0 cu ft | Aluminum | None listed | Lifetime limited | $1,333 |
| Weather Guard 178 | Low Profile Lo-Side, 56 in | About 56 x 17 x 13 in | 4.0 cu ft | Aluminum | Drain plug | Lifetime limited | $1,161 |
| Weather Guard 174 | Lo-Side, 56 in | About 56 x 17 x 13 in | 4.0 cu ft | Aluminum | Drain plug | Lifetime limited | $981 |
| Weather Guard 180 | Low Profile Lo-Side, 41 in | About 41 x 17 x 13 in | 3.0 cu ft | Aluminum | Drain plug | Lifetime limited | $989 |
| UnderCover SwingCase | Swing-out wheel-well case | Upper case 29 in long, lower case 15 in long, 8 in wide | 1.5 cu ft | ABS composite | None listed | 1-year limited | $219.99 |
Standard twin of the 121
Weather Guard 127 Aluminum Crossover Truck Tool Box, Full-Size Standard, Bright Aluminum (127-0-04)
From $1,340 · Same 72 by 20 by 18 inch body and 11.0 cubic feet, standard style.
One 121 owner with a crew cab Silverado put a number on the difference. It is the owner's own measurement, not the maker's:
“the difference between the standard and low profile is the distance from overhang and bottom of toolbox, standard is around 11 inches and the low profile is 13 inches.”
Weather Guard 121 Aluminum Crossover Truck Tool Box, Full-Size Low-Profile, Bright Aluminum (121-0-04) owner · 5 out of 5 stars
On that owner's reading, the low profile body reaches about 2 inches further below the overhang than the standard one. Treat it as one owner's reading and measure your own truck.
Does a low profile box clear the rear view?
Not always. One 131 owner says the box still cuts into the mirror view, and a 121 owner found it less low than expected:
“The low profile unit is large enough to affect rear view mirror field of vision, but it is acceptable.”
Weather Guard 131 Aluminum Crossover Truck Tool Box, Mid-Size Low-Profile, Bright Aluminum (131-0-04) owner · 5 out of 5 stars
“Excellent tool box, it's not as "low profile" as I was expecting.”
Weather Guard 121 Aluminum Crossover Truck Tool Box, Full-Size Low-Profile, Bright Aluminum (121-0-04) owner · 5 out of 5 stars
Low profile tool box picks
These picks use the listed specs, each listing's truck list and the owner reviews on file. The full range is in our Weather Guard tool boxes collection.
Best overall: Weather Guard 121
Best overall
From $1,340 · Full-size low-profile aluminum crossover with 11.0 cubic feet.
The 121 is a single-lid aluminum crossover with a five-piece welded body and a reinforced front. The lid opens near 90 degrees on gas struts, and clamps and hardware are included. Of its 144 reviews on file, 117 are five-star. Six of those reviews report latching trouble, from a lid that would not latch without body weight on it to latch screws that came loose, and two owners fixed theirs with shims or by adjusting the latch rod. One 121 owner notes that the lid's seal drain ports feed into the side trays, which showed only during a pressure wash.
Pros
- Lists the same 11.0 cubic feet as the standard 127
- Reinforced front and welded strut shields
Cons
- Six owners on file report latching trouble
- Made for full-size beds only: check your rails and the space behind the cab first
Skip it if your truck is mid-size: the 131 is the crossover listed for those.
Steel option: Weather Guard 120
Steel option
Weather Guard 120 Steel Crossover Truck Tool Box, Full-Size Low-Profile, Brite White (120-3-04)
From $1,343 · The 121's size and capacity in Brite White steel.
The 120 lists the same 72 by 20 by 18 inch body and 11.0 cubic feet as the 121, with heavy-duty formed steel in a Brite White ARMOR TUF finish. Ten reviews are on file, nine of them five-star.
Pros
- Steel body in Brite White ARMOR TUF
- Same listed body and 11.0 cu ft as the 121
Cons
- 10 reviews on file, against 144 for the 121
Skip it if you want bare aluminum: the 121 is the same size.
Best for mid-size trucks: Weather Guard 131
Best for mid-size trucks
From $1,333 · 62-inch low-profile crossover with 8.0 cubic feet.
The 131 is the mid-size crossover: 62 by 20 by 18 inches with 8.0 cubic feet, in the same aluminum build as the 121. It appears on the Colorado, Canyon, Ranger, Tacoma and Frontier pages. Nine reviews are on file, eight of them five-star. One owner mentions a mounting clamp that twisted during install. For less height, the 154 Mid-Size Slim, from $1,293, lists 62 by 20 by 13 inches and 7.0 cubic feet for the same five trucks. Its listing says slim, not low profile.
“Construction still leaves plenty of room below the unit to accommodate long items on the bottom of the truck bed.”
Weather Guard 131 Aluminum Crossover Truck Tool Box, Mid-Size Low-Profile, Bright Aluminum (131-0-04) owner · 5 out of 5 stars
Pros
- Listed for the Colorado, Canyon, Ranger, Tacoma and Frontier
- Long items still fit under it, says an owner
Cons
- 8.0 cu ft, 3.0 less than the 121
- One owner says it cuts into the mirror view
Skip it if your truck is full-size: the 121 and the 127 are the boxes listed for those.
Low profile Lo-Side for full-size trucks: Weather Guard 178
Low profile Lo-Side, full-size
Weather Guard 178 Low Profile Lo-Side Truck Tool Box, 56" Bright Aluminum Diamond Plate (178-0-04)
From $1,161 · 56-inch Low Profile Lo-Side that sits on one bed rail.
The 178 is the 56-inch Low Profile Lo-Side: about 56 by 17 by 13 inches with 4.0 cubic feet in welded aluminum diamond plate, mounted on one bed side rail. A gas strut lifts the lid to about 90 degrees, the lock is a keyed cylinder with a recessed red push-button and the listing gives it a drain plug. It appears on the full-size truck pages only, and no owner reviews are on file. The standard 174 lists the same size and capacity, costs less at $981 and averages 4.8 from 16 reviews on file, so choose the 178 only if you want the low profile version.
Pros
- Low profile Lo-Side with a drain plug
Cons
- No reviews on file
- Costs more than the standard 174 for the same listed size
Skip it if your truck is mid-size: the 180 is the Lo-Side listed for those.
Best low profile box under $1,000: Weather Guard 180
Best low profile box under $1,000
Weather Guard 180 Low Profile Lo-Side Truck Tool Box, 41 in Bright Aluminum Diamond Plate (180-0-04)
From $989 · 41-inch Low Profile Lo-Side listed for full-size and mid-size trucks.
The 180 is the short Lo-Side: about 41 by 17 by 13 inches with 3.0 cubic feet, built and mounted like the 178. Its listing has the longest truck list here, 16 truck pages including the Maverick. Its one review on file is five-star.
“This box did not mount easily to my f150 because I have a plastic bed liner that takes up a good portion of space between the bed and bed rail.”
Weather Guard 180 Low Profile Lo-Side Truck Tool Box, 41 in Bright Aluminum Diamond Plate (180-0-04) owner · 5 out of 5 stars
Pros
- Listed for 16 truck pages, Maverick included
- Under $1,000
Cons
- 3.0 cu ft
- One owner with a plastic bed liner needed their own hardware
Skip it if you carry long tools: the body is 15 inches shorter than the 178 and holds 3.0 cubic feet against 4.0. The standard 174 is also under $1,000 and is 56 inches long.
Best with a tonneau cover: UnderCover SwingCase
Best with a tonneau cover
UnderCover SwingCase Swing-Out Truck Bed Toolbox
From $219.99 · Swing-out case that bolts in between the wheel well and the tailgate.
The SwingCase is a swing-out case in impact-resistant ABS composite with 1.5 cubic feet and a load rating of up to 75 lb. The lid has a key-lockable rotary handle and a weathertight seal, the listing gives a 1-year limited warranty and install is listed at 30 minutes or less. Of its 141 reviews on file, 122 are five-star.
“My electric roll top glides right over it so it's low profile.”
UnderCover SwingCase Swing-Out Truck Bed Toolbox owner · 5 out of 5 stars
“These boxes are plastic and not a very hard plastic. Although it has a lock on it someone could very easily break into it.”
UnderCover SwingCase Swing-Out Truck Bed Toolbox owner · 3 out of 5 stars
Pros
- Our listing says it works with most tonneau covers
- Key-lockable with a weathertight seal
Cons
- 1.5 cubic feet, half the smallest Weather Guard box here
- ABS composite, not metal
- One 3-star owner on file says someone could easily break into it
Skip it if you carry long tools or want a metal box.
Full-size or mid-size: which low profile box fits your truck
Fit follows the truck list on each listing. Measure before you order: the 72-inch crossovers span the bed from rail to rail, a Lo-Side needs the usable length of one rail and every Weather Guard box needs space behind the cab. This sizing guide covers measuring.
| Truck size | Listed trucks | Crossover | Lo-Side |
|---|---|---|---|
| Full-size | Silverado 1500 and HD, Sierra 1500 and HD, F-150, Super Duty, Ram 1500, Ram 2500 and 3500, Tundra, Titan | 121, 120 and 127 (72 in) | 178 and 174 (56 in), 180 (41 in) |
| Mid-size | Colorado, Canyon, Ranger, Tacoma, Frontier | 131 (62 in) | 180 (41 in) |
The 180 is also listed for the Ford Maverick. The SwingCase is listed for the Colorado, Canyon, Ranger, Tacoma, Tundra, F-150, Super Duty, Silverado, Sierra and Ram 1500. Parts stop at 2023 on the Tacoma and 2022 on the Colorado and Canyon, and none is listed for the 2008 to 2018 Silverado and Sierra 1500, the 2008 to 2019 HD trucks or a Ram 1500 before 2019. Its fitment table lists the factory options it does not fit, such as a RamBox.
Low profile boxes and tonneau covers
Crossovers and Lo-Side boxes both use rail space. The SwingCase mounts between the rear wheel well and the tailgate. Our listing says it works with most tonneau covers, though a few truck kits name covers that do not suit them, as that truck's page shows. One owner says an electric roll-top cover glides right over it. If you run a cover, start with the best tool boxes for use under a tonneau cover and check the cover maker's fit notes before adding any rail-mounted box.
Locks, mounting and keeping water out
Every Weather Guard box here lists the 1Key UltraLock, a tamper-resistant lock that is keyed alike. The crossover listings call it a push-button lock and the Lo-Side listings a keyed cylinder with a recessed red push-button. Weather Guard's own video shows how it works.
Under-rail clamps and hardware come with each Weather Guard box here, and the listings say no drilling is required. Two Lo-Side owners still used a drill: a 174 owner and a 180 owner with a plastic bed liner. Our crossover pages put an install at about 20 to 30 minutes. The SwingCase uses side-specific brackets, and its listing says some trucks need drilling.
For water, the crossovers list a full-perimeter D-shaped weather strip and the Lo-Side boxes a multi-ridge seal and a drain plug. Weather Guard puts a limited lifetime warranty on its truck boxes for manufacturer defects. The SwingCase is 1 year limited. Full mounting steps are in our truck tool box install guide. For lock options, mounting checks and keeping a box dry, read our guide to securing a truck tool box.
Low profile boxes versus the other box types
A crossover gives the most room here, up to 11.0 cubic feet, while a Lo-Side uses one rail. For the other types side by side, see our roundup of the best truck tool boxes.
Frequently asked questions
What does low profile mean on a truck tool box?
It means the box sits lower above the bed rails than a standard box. In Weather Guard's range the low profile and standard twins list the same outside size and capacity: 72 by 20 by 18 inches and 11.0 cubic feet for the 121 and the 127.
What is the best low profile tool box for a full-size truck?
The Weather Guard 121, from $1,340, is our pick, with 11.0 cubic feet and 144 reviews on file averaging 4.8. The 120 is the steel version.
What are good low profile tool boxes for a mid-size truck?
The 131 crossover, from $1,333, is listed for the Colorado, Canyon, Ranger, Tacoma and Frontier. The 41-inch 180 Lo-Side, from $989, is listed for those trucks too.
What is a Lo-Side tool box?
A Lo-Side box mounts on one bed side rail and leaves the rest of the bed open. Here it comes in 56 inches (4.0 cubic feet) and 41 inches (3.0).
Does a low profile tool box block the rear window?
It can affect the mirror view. A 131 owner says so but finds it acceptable, and a 121 owner found the box less low than expected.
Is there a black low profile truck tool box?
Black is a finish, not a style. The Weather Guard low profile boxes here are listed in bright aluminum (121, 131, 178 and 180) or Brite White (120). The UnderCover SwingCase is the black box on this list.
Are truck bed tool boxes worth it?
For tools that ride in the truck every day, yes: a locked, sealed box keeps them out of the cab and out of the weather. Skip a crossover if you need the full bed length behind the cab, and pick a Lo-Side or the SwingCase if you run a tonneau cover or want the bed floor clear.
Find a low profile box that fits your bed