A wheel chock for restraining movement of a vehicle tire on a supporting grating during transit includes a base, a grate lock mechanism for locking the base to the grating, and a ramp on the base for engagement with a circumference of a vehicle tire. A strap connected with the base is extensible around the vehicle tire to help restrain movement of the tire on the grating. The chock includes a retractor for retracting the strap and for taking up slack that forms in the strap during transit.