✔100% IPX7 Waterproof: With the IPX7 waterproof function, remote shock collar for dogs receivers could use to train dogs in various water activities, it works well even if immersed in water; you don't have to worry about the shock collar breaking down after soaking. With this dog shock collar you do not have to worry about taking your dog for swimming, a walk in the rain, or even to the beach for training. There is no chance that your dog will be harmed by electrical leakage. ✔4 training modes: The dog training collar support 4 different types of training which you can use to manage incorrect behaviors of your dog; LED LIGHT MODE helps you to locate your dogs in the dark environment; VIBRATION & STATIC SHOCK MODE is adjustable from 0-99 levels, and they should begin at a lower level to avoid harming the dog. When your dog is well trained, the TONE MODE is all you need to effectively interact with your dog. NOTICE: Shock mode should be the last choice. ✔1650ft range dog training: the electric dog collar with remote control range of up to 1650 feet in open spaces. Therefore, by the sport dog shock collar with remote for large dogs,you can train your dog easily in parks, or in your backyard. You can also use this dog collar shock to correct dogs' barking, walking, leash training, sitting, aggression and other behavioral obedience. You can train 3 dogs with one transmitter, but only one receiver is included. ✔Fast Recharging & Auto Power Saver: the Controller and Receiver have built-in rechargeable batteries, and the charging interface is a micro USB, common with smart-phones. The recharge time is approximately 2 hours. If there are no operations within some minutes, the remote and receiver collar will automatically enter sleep mode to save power. Under normal circumstances, with the small dog shock collar on, one charge can allow usage up it 15-20 days continuously. ✔One-year warranty: The dog barking collar comes with a one-year warranty provided by LINNSE. We offer 100% refund / free replacement for these pet trainer shock collar if we could not meet your satisfaction. Please contact us if you have any questions of the dog e collar. We will try our best to help you. Moreover, the shock collar for large dogs, small dogs is easy to adjust according to your dog’s neck.