The one pictured mounts across the 200lb toboggan, it fastened to the sides. The whole affair is then turned sideways to shoot. This rig doesn't work without being mounted. The little one was the 100lb toboggan as I recall...your pic shows him with the mount I sent just laying in the bottom of a flat smooth toboggan...like a set of runners. I don't recall if or how they mounted on that one. I just remember they were to be loaded with the heavies stuff in the platoon, the MG ammo and MG, and pulled by weapons det. That means 200 lbs of gear on that tiny rig digging into the snow, or distribute the weight on the big ones and share the load...