Boyt Electronic Dog Training Add-A-Collar - The MR1001 Add-A-Collar is compatible for use only with the MR1000 Electronic Dogy Training System. It is designed with five training modes, (Light, Tone, Vibration, General and Boosted Stimulation) and a signal transmission range of 1000 yards line of sight. The collar is powered with a rechargeable lithium battery that can be fully charged within approximately 2 hours. It features momentary and continuous correction, LED Spotlight Mode and Stimulation Safety Lock. The collar offers 16 distinct tone levels, 36 vibration levels and 99 stimulation levels. The waterproof collar is length adjustable from 6in - 27in to fit most dogs up to 100 lbs. Detachable, long contact probes are included. Features Compatible only with MR1000 Electronic Dog Training System Use as a Spare or Two Dog Training Capability withMR1000 Five Training Modes: Light, Tone, Vibrate, General & Boosted Stimulation Continuous and Momentary Correction Options Up to 1000 Yard Signal Transmission Range in Open Space Stimulation Safety Lock Fast Charging Rechargeable Li-ion Battery Battery Life: 16 Days Night Vision Light Adjustable Collar Size: 6in - 27in Includes Detachable Long Contact Probes