With an expansive three quarter-mile range, the Dogtra 2300NCP Expandable E-Collar Dog Training System meets the needs of advanced-level training for hunting, competition, or police K-9 work. This tried-and-true multipurpose E-collar includes rugged receiver with low-high stimulation. Choose from up to 127 levels for precise and gradual control using a patented rheostat dial with LCD display on the handheld transmitter. Ideal for training both mild and stubborn dogs, the 2300NCP E-collar features 2-dog expansion. Intuitive controls include buttons for nick and constant stimulation and pager vibration. IPX9K waterproof rating. Expansive three quarter-mile range Low-high stimulation 127 stimulation levels Handheld transmitter with rheostat dial Ideal for both mild and stubborn dogs Nick and Constant stimulation Pager vibration IPX9K waterproof rating