Dogtra E-Fence 3500 Add On Collar...

RANGE: The range of the E-FENCE 3500 receiver goes up to 40 acres. It’s an effective underground containment system that allows your dog the freedom to run around whilst also being protected on your property.
PAGER & CORRECTION MODE: This underground containment system comes with the option to make a choice between two types of modes. The Pager Only mode provides a HPP (High-Performance Pager) vibration, which offers a clear vibration to alert dogs whilst near the boundary. The Pager/Correction mode provides both a vibration followed by a correction when the dog approaches the boundary area.
IPX9K WATERPROOF CERTIFIED: The E-FENCE 3500 receiver is IPX9K waterproof certified, because of this it passed the International Protection Marking system. Products are verified if they may be able to stand a close-range high-pressure liquid spray from 4 angles (pressure of 80-100 bars and a temperature of 176°F).
EXPANDABILITY: This receiver is designed for dogs 15 pounds and up and is perfect for small to medium dogs with its durable design. It may be added to an existing EF-3500, in order that more than one dogs can use the same system.
RECHARGEABLE BATTERIES: The E-FENCE 3500 receiver has rechargeable batteries that may be abruptly charged in two hours.