Dubro's Tru-Spin Prop Balancer can balance your aircraft props, boat propellers, spinner backplates, car wheels or tires, as well as many other items in the hobby industry. Features: Completely Adjustable Propeller Balancer Precision-Machined Rotating Wheels to Assure Perfect Balance Easily Unique Over/Under Set-Up Option Accommodates Even Large-Scale Props Includes:One Tru Spin Prop Balancer