The Porta-Glide Dolly Sled Set from Porta-Jib includes two 30.5" dolly sleds. Each sled features 16 wheels, eight on each side. The wheel assemblies can be detached and bolted to other platforms or to a speed rail plate (available separately). Each dolly sled features one locked arm and three floating arms. The floating arms can be locked by adding a 3/8-16 x 0.75" screw (available separately) through the access holes.