The Dogtra EDGE is a fully customizable and expandable, up to a 4-dog system, e-collar, designed for professionals and serious amateurs. It features a 1-mile range, 2-hour rapid charge batteries, fully waterproof receiver and transmitter, and built-in high intensity LED location lights on the receiver. The EDGE comes equipped with stimulation modes in Nick and Continuous, and a non-stimulating Pager vibration and Location Light mode. The high intensity Location Lights will help you locate and track your dog in the darkest of nights. The Dogtra EDGE is a durable, high performance system that exceeds the expectations of professionals and serious amateurs alike.