F4B-1 (Boeing Model 99) The F4B-1 was built using typical construction techniques of the day with a welded truss fuselage with formers and longerons to define the aerodynamic shape.

The Pratt & Whitney R-1340 nine-cylinder radial engine was uncowled and sported prominent cooling fairings behind each cylinder which were later removed in service.

F4B-2 (Boeing Model 223) The F4B-2 was similar to the F4B-1 but incorporated a Townend ring cowling around the engine.

A spreader bar was incorporated between the landing wheels and the tail skid was replaced by a castoring tailwheel.

Some F4B-2s received F4B-4 style vertical fins and rudders to address poor directional stability.

F4B-3 (Boeing Model 235) The F4B-3 represented a significant departure in design from the earlier versions of the F4B.

From the engine mount aft to the rear of the fuel tank bay, the structure was welded steel truss, while the fuselage aft of the fuel tank bay was constructed of stressed skin, semi-monocoque aluminum alloy.

F4B-4 (Boeing Model 235) The F4B-4 was nearly identical to the F4B-3, but incorporated a larger vertical fin to address the directional stability issues that plagued the F4B from its inception.

F4B-5 (Boeing Model 261) A detailed specification was written for an F4B-5 as a minor development of the F4B-4 but was not proceeded with.

By direction of MAJ Roy S. Gieger, Officer-in-Charge of Marine Corps Aviation, all VF-10M F4B-4s on strength be transferred to VF-9M at Quantico.