The rugged, all steel Safety Wheel Chocks are quickly and easily attached. Assembly is simply placed on exposed rail head and extension arm is lowered to horizontal position to secure device on rail. Assembly's long extension arm extends large diameter warning sign up to the side of car to permit maximum visibility. Standard finish is bright maintenance-of-way yellow.W-C-H Wheel Chocks assure safe, secure blocking of standing cars. Chock is easily installed by placing it on the rail and pushing it directly against the standing wheel. The cams of the chock are tightened and set by rotating the handle to the locking position.