For pets under 40 pounds. 10 levels of stimulation correction plus tone-only button. Correction levels: 400 volts - 6000 volts. 100 yard range. Waterproof receiver, water resistant transmitter. Receiver uses two 3-volt CR2032 batteries; transmitter uses a9-volt alkaline battery (both included). Transmitter has correction dial and red light on face. Frequency: 303.825 MHz. Pop off battery cover and belt clip is on back. Receiver collar has antenna running through strap, light on side, and power push button. Red light serves as low battery indicator. Battery life of up to 30 days. Will retain program memory if batteries die or if they are removed.