The DanaDolly Original 150mm Kit with 100 & 150mm bowl adapters and original style track ends is a heavy duty camera dolly platform that rides on 16 custom modified soft polyurethane wheels that resist flat spotting and use ABEC-7 rated precision bearings providing you with extremely smooth dolly shots. The wheel trucks swivel, allowing the dolly to ride on available straight or curved track, which you must source separately. The manufacturer recommends using standard speed rail or Schedule 80 aluminum pipe of compatible size. The dolly includes two original style track ends, which accept inch and a quarter pipe (standard speed rail) and fit into available standard Junior stand receivers. A center support is included for long track runs or when using heavy cameras.The dolly platform is machined from aluminum and features a standard Mitchell mount including a 2.75" center hole with a machined key way. The included 100mm and 150mm bowl adapters allow you to mount fluid heads with standard 100mm or 150mm leveling balls. The platform incorporates one 3/8" through hole, one 1/4"-20 threaded hole and one 3/8"-16 threaded hole on each side of the dolly platform for a total of 6 accessory mounting holes. The Dana Dolly is designed and manufactured in the USA.