Protect your RV/caravan trailer with AMPLock TLS model. This Amplock is made for 2 5-16’’ ball with inverted coupler style (underslung). Make sure that your coupler width is 4.75'' wide or less. We use high quality materials: steel and stainless steel to provide years of durability and dependability. We use a disk-based lock coupled with a control and identification key system. Each AMPLock lock has its own unique key. With your AMPLock you will have a good protection for your goods.