Provides added stabilization and prevents tire shift by applying opposing force to tandem tire applications. As opposed to other chocks, the X-Chock works with the tires natural movement instead of against them. Fits even the tightest of applications retracting down to 1-3/8" and extends to 12". X-Chock has a rust inhibitive coating, lightweight, easy to store, made in USA and a plated ratchet wrench with comfort bumper is included. Lockable for added security with pad lock 28015 (not included).