Aetertek At-216w 600 Yard Remote Dog Training Shock Collar 7 Levels Shock,Strong Vibration, Warning Beep Correction Methods 3 Dogs 550 meters remote control range, 3 dogs training shock collar Water-resistant receiver (Not waterproof, please DON'T IMMERSE IN WATER ) Adjustable TPU strap, it is suitable for small, medium and large dogs weighing from 15 to 150 lbs. 3 modes: Warning Beep Tone, Vibration, 7 levels of adjustable Shock. Static shock at the highest intensity is adequate for extra large or stubborn dogs, and mildest shock will not harm even the smallest dogs