The K9-400 K9 Handler is a 3/4 mile range trainer loaded with unique features making it the most humane and effective trainer available with the smallest rechargeable dog training collar receiver in the world. But, don't be fooled by the small receiver size 2""X1.5""X1"" 2.4 ounce, it provides plenty of stimulation for most dogs. The unique COS (control of stimulation) technology provides very clean stimulation without the normal head jerking often found with other training collars. The tapping sensation employed is similar to vibration, but more intense making it a good substitute to the stimulation. The bungee collar provides added comfort and contact reliability unmatched in the e-collar industry while the stop watch style transmitter is wrapped in black skins for discreetness. The night tracking light is controlled by the transmitter allowing the user to flash or continuously light up the collar receiver for locating your dog after dark. Lost transmitter beeper can be turned on to help locate a misplaced or lost transmitter. The transmitter even floats so don't worry if you drop in the lake. The K9-400 E-Collar will turn a smart stubborn dog into a genius. 100% Satisfaction Guaranteed. Proudly Assembled in the USA.