The Firstlaw Fitness Joist Mount offers you an efficient and economical solution for suspending your heavy bag, whether at home or in your gym. It features a built-in compression spring system, which allows your heavy bag to swivel across a full 360-degree range, while effectively dampening noise and vibration. Designed to support heavy bags between 120 and 200 pounds, this sturdy mount easily installs onto the bottom of an exposed floor joist. Additionally, you can enjoy peace of mind with a lifetime warranty!