Designed for in-the-field training or hunting with close working dogs, the SportDOG Brand FieldTrainer 425X Electronic Dog Training Collar helps you and your dog focus on training. SportDOG's smallest and lightest FieldTrainer e-collar, the 425X puts 21 levels of static stimulation, tone, and vibration corrections in hunter's hands. System works with up to 3 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). Waterproof collar design is submersible to 25' thanks to DryTek technology. Collar features rechargeable lithium-ion battery for 50-70 hours of use per charge.Manufacturer model #: SD-425X. Dog training collar for close working dogs Smallest and lightest e-collar in SportDOG's FieldTrainer line Correct with tone, vibration, or one of 21 static stimulation levels Expands to 3 dogs with Add-A-Dog collars (not included) Easy-to-use collar design DryTek waterproof design - submersible to 25' Rechargeable lithium-ion battery in collar