Humane and Harmless System - The no bark collar has an adjustable sensitivity and 3 training modes. Rechargeable & Water Proof - Built-in USB rechargeable battery. LONG-LASTING BATTERY LIFE - Rapid Charging Lithium Ion Battery Provides a long lasting Battery Life. Auto Power Protect Mode Helps Conserve Battery Life When Not In Use. Can be used continuously for 14 days. LED Display, Electric Ultrasonic Training Collars.