Abstract: A strap winding mechanism for the winding of truck load straps and the like, in the form of an L-shaped frame having first and second legs in right angle relation with the first leg being demountably clamped in an upright position to any selected stake hole of a conventional flat bed truck so that the second leg extends horizontally from the truck bed. Intermediate the ends of the second leg, a strap reel handle and strap reel assembly are journaled for relative engagement during the winding operation.A strap guide is arranged at the outboard end of the second leg for guiding the strap onto the reel. The strap reel handle and strap reel assembly may be interchanged in position or removed, and the strap guide may be attached to extend from either side of the second leg or completely removed, for ease of use and convenient storage.