Aetertek Time-tested 216 Dog E-collar Waterproof Dog Shock Collar Remote Dog Training System 7 Levels of shock + vibration + beep For one small medium or large dogs Aetertek 216D dog shock system with remote. Features 7 levels of shock, vibration and beep to eliminate all bad behaviors. Can train up to three dogs with one remote.(need additional collars). Aetertek collar use the most advanced design, electromagnetic induction switch solution, on the power ON/OFF switch to ensure unlimited accurate switch, more convenient and reliable. Aetertek receivers DC base adopt embedded injection molding process, and equipped with high-precision-waterproof ring with built-in guide slot , ensured waterproof effect over 3 hours underwater 50cm. Fits all dogs from 15 to 150lbs with a collar size from 14 to 24 inches long. 100% waterproof and rechargeable collar,your dog can swim or get out on the rainy days Very safe and humane collar, the vibration stops most of the dog's bad behavior .