Valterras A10-0914 Big Chock keeps your trailer or RV in place with integrated grooves that grip your tires for added stability. Rubber padding on the bottom provides slip resistance for extra security. The body is constructed of durable, solid polyethylene for strength, and includes a nylon cord to easily remove the chock. Dimensions: 9-1/2 length x 8-1/2 width x 4-1/2 height.