C.T.Johnson TCL1-YL Deadbolt Blockhead Trailer Coupler Lock Johnson - Deadbolt Blockhead Trailer Coupler Lock For 1-7/8 inch and 2 inch Couplers Maximum security for unattended trailers Hi-tech materials redefine the traditional lip engaging coupler lock Extruded, tempered aluminum body provides superior strength to weight ratio, a distinctive look, and great value Simple, rugged push button lock mechanism