Protect your trailer lunette ring with the best coupler lock, AMPLOCK's exclusive locks are the most durable and reliable on the market today. Our unique product is made with the following high quality material : stainless steel to provide years of dependability and durability. The locks are made of good rust resistance insuring long term outdoor use in different climates. To increase security, each AMPLOCK lock has its own unique key and we use a disk-based lock coupled with a control and identification key system. You can enjoy life without worries with the best trailer coupler lock. Our various models are mold to fit the specific shape of your trailer lunette ring when unhitched, so your AMPLOCK trailer coupler lock is the perfect theft deterrent. **Make sure you choose the right model for your trailer coupler size and type, referring to pictures provided (photos are for visual reference only) or to our website www.amplock.com **