PLEASE READ: THIS COLLAR ONLY WORKS ON THE BASICS TRANSMITTER, WHICH IS WHITE WITH A BLACK HOUSING. NOT COMPATIBLE WITH G1 or G2 TRANSMITTER. SEE MAIN IMAGE. Safe and Comfortable: Includes 2 Sets of Contacts (1x Medium and 1x Large Contacts, w/ Replacement tool and Tester) Waterproof: This Collar is Not Only Waterproof, but Also is Submersible. Collar Function and Correction Will Not be Effected By Water. Rechargeable: The Collar Features a Rechargeable Battery. Charging Cable Included in Package. Please contact our Service Center at 800-305-6116 if you need additional components for your existing system.