"Designed for close-up training and hunting in waterfowl areas, the SportDOG Brand WetlandHunter 425X Electronic Dog Training Collar helps you and your dog focus on training. SportDOG's smallest and lightest WetlandHunter e-collar, the 425X puts 21 levels of static stimulation, tone, and vibration corrections in hunter's hands. Realtree Max-5 camouflage finish and DryTek waterproof technology (collar unit submersible to 25') make this collar system perfect for waterfowl-huntin' dogs. System works with up to 3 hunting dogs (with purchase of additional Add-A-Dog collars - not included) up to 500 yards away. Easy to use controls gives a trainer correction control with a simple twist of a dial and push of a button, allowing the operator to focus on the dog(s). Collar features rechargeable lithium-ion battery for 50-70 hours of use per charge. Fits dogs 8 lbs or larger with neck sizes 5""-22"" and 3/4"" thick. Dog training collar for close working waterfowl dogs Smallest and lightest e-collar in SportDOG's WetlandHunter line Correct with tone, vibration, or one of 21 static stimulation levels Expands to 3 dogs with Add-On collars (not included) Easy-to-use collar design Realtree Max-5 camo finish DryTek waterproof design - submersible to 25' Rechargeable lithium-ion battery in collar"