3-Dog System: Continuous Stimulation, Momentary (Nick) Stimulation, Positive Vibration The Micro-iDT is a lightweight trainer that offers simple controls, but advanced features so that this unit can grow with your dog's training needs. The rugged micro-sized collar unit and transmitter fit in the palm of your hand. The comfortable waterproof collar fits small to large dogs. The Micro-iDT Series represents the absolute latest technological advancement in the Electronic Dog Training World. It offers Maxx-Range, an internal FM radio frequency antenna woven in the collar. With up to a 500 yard range, they are perfect for field or household use. The Micro-iDT Series collars feature sixteen levels of stimulation intensity, with an easy 'no look' clicking stimulation dial. Easy one hand held operation allows for maximum control and safety. Features: - 500 Yard Range - 16 Levels of Intensity adjusted from the Transmitter - Digital technology to Maximize Power - Maxx-Range Internal Collar Antenna System - Lightweight, Compact Collars and Transmitters - Fits extra-small to large dogs - Built in Magnetic ON/OFF system - Rechargeable Ni-MH Battery System in the collar - 9V Replaceable battery in the transmitter - Completely Waterproof Collars - Weatherproof transmitters Control Options: - Micro-iDT 3000 Momentary "Nick" Stimulation - Continuous Stimulation - Positive VibrationTM Three collar receiver unit2 included