This is a reliable and safe dog fence system. It provides WiFi connection instead of wired connection, which makes the installation much easier than before. The transmitter in the center provides a range of up to 500 meters. In this larger space, your dog can go anywhere freely and safely. You would not worry about their activities limited or lost. It can be widely used for dog training at home or educational outing.Features:- Completely wireless system- A circular signal area based on the center of the transmitter and remote controlthe range is up to 500 meters.-Unlimited number of receivers supported at the same time.-100 levels of transmitter signal intensity to adjust the range of the remote control.-The current intensity will be displayed on the transmitter screen.-Very easy to do pairing for transmitter and receiver.- Waterproof and rechargeable collar receiver.Progressive warning tone.-Multiple collar operation.- Water-resistant TPU collar fits dog neck sizes under 22'.Specification:Product Name: Animal FenceModel: KD-661White colorMaterial: ABS (acrylonitrile butadiene styrene)Transmitter size: 14x8x3cm (L x W x H)Receiver size: 7x4x2.5cm (L x W x H)Bracelet length: 70cmBracelet width: 2cmPower Input: 100-240V / 50-60Hz / 0.35AOutput: 5V / 1APlug: US PlugPackage Included:1 x Wireless Transmitter3 x Receiver Collar3 x Adjustable TPU Strap1 x charger12 x Metal Contact Probes2 x screws2 x screw holder3 x LED test light1 x User ManualNoticed:1.The wireless fence system is intended for dogs only.2.Low battery may cause intermittent operation. Do not use it and charge it immediately for low battery.3. Do not leave the collar on your dog for more than 1 hour per day.4. Keep the receiver collar away from children.5. Read all instructions before using this product.Product principle: When the dog goes out of the set activity range, the receiver automatically starts the training function. Sound alert first, then electrostatic stimulation to remind the dog back to the safe area.Suggest:1. For the first time using, it is recommended to set a wide range of activ