Abstract: A portable detachable side mounting load strap rotary tensioning device 1 for mounting transversely on a load binding strap 2, the detachable portable side mounting load strap rotary tensioning device 1 comprising a frame 3 and, a rotary tensioning mechanism 4, and counter-rotation tabs 7 defining an opening, the rotary tensioning mechanism 4 located proximate one end of frame 3 and the counter-rotation tabs 7 located proximate the opposite end of frame 1, the rotary tesioning mechanism 4 comprising a rotating shaft 10 having a strap receiving slot 14, characterized in that the strap receiving slot 14 in the rotating shaft 10 and the opening between the counter-rotation tabs 7 are located for mounting traversely on a load binding strap 2.