Hawk
Fits Full-Sized Trucks w/ 6.5 ft bed
Common examples of which a Hawk will fit on:
Ford F150 & F250
Chevy GMC 1500 & 2500
Ram 1500 & 2500
Toyota Tundra
Nissan Titan
Fleet
Fits Mid-Sized Trucks w/ 6 ft bed
Common examples of which a Fleet will fit on:
Toyota Tacoma
Ford Ranger
Chevy Colorado
Nissan Frontier
2000-2006 Tundra (Access Cab)
Grandby
Fits Full-Sized Trucks w/ 8 ft bed
Common examples of which a Grandby will fit on:
Ford F-250 & F-350
Chevy GMC 2500 & 3500
Dodge Ram 2500 & 3500
Eagle
Fits Mid-Sized Trucks w/ 6 ft bed
Very comparable to the Fleet in terms of fitment, but the Eagle model is 6 inches narrower. This takes out a little bit of interior room but also has its advantages compared to a Fleet. Some of these include better visibility while driving, a minor weight reduction, and a potential slight boost in MPG.
Best for: '00-'06 Tundra Access Cab and '95-'04 Tacoma
Also fits on the Ford Ranger, Chevy Colorado, and Nissan Frontier
Raven
Fits Full Sized Trucks w/ 5.5 ft bed
The Raven fits similar to a Hawk but is slightly shorter to fit better on short bed full-size trucks. Some examples are the short box F-150 (see picture) and the short box GMC Sierra 1500.
Keystone
Fits Full-Sized Trucks w/ 8 ft bed
Similar to a Grandby, this fits long bed full-size trucks. However, the difference is this Keystone is 9' long (compared to 8'). This offers maximum comfort inside but since it is the largest camper Four Wheel has to offer, it will stick out ~12 inches from the end of your truck bed.
Commonly fits on a Ford F250 & F350, Chevy GMC 2500 & 3500, and a Dodge Ram 2500 & 3500
Swift
Fits Mid-Sized Trucks w/ 5 ft bed
The Swift is a very similar camper to the Fleet but it's designed for the same trucks with the shorter 5' beds. The most common example is a Double Cab Tacoma Short Box.