Chock includes the T-base and a security pin that can be used to lock your bike to the chock (lock not included) Flush mount T-base fits all trailers and truck beds with no hassle of aligning separate cleats Chock mounts to T-base at four points for strength and stability Ultra-durable powder-coat finish Large models fit street/supermoto applications and with clearance for all disc brakes All mounting hardware and instructions included