The VIV-VPT-500 Professional Video Tripod Dolly from Vivitar accommodates most video and camera tripods on the market and has a load capacity of 55 lb. It has leg extensions of 15 to 24". On top of each leg extension there is a leg lock that can adjust to the tripod's leg diameter.
Once the tripod is fastened and secured into place, the 2.5" hard rubber wheels move freely to follow your subject. The wheels can lock into place by stepping on the wheel locking system. The dolly has a foldable design with a closed length of 20", and it can be transported easily with its carrying handle.