Trimax 4010208 SXT3 Premium Stainless Steel 5/8in Key Receiver Lock Made of high quality 100 percent stainless steel O-ring seal and water tight cap help seal out dirt and corrosion 1/4 turn locks and unlocks head Lock can not "pop" open Lock can not be false Locked The 5/8" pin fits all Class III, IV and V receiver hitches O-ring keeps water, grime and dirt out of locking mechanism to ensure years of use Protective rubber cap protects keyhole from water, grime and dirt Strongest locking pin on the market Type A key which is a spring loaded, 7 pin, high security key. Resists attempted drill outs. Rugged and durable, the key will not bend or break.