https://www.extremedogfence.com/shop/pet-accessories/collars/extreme-dog-fence-hyper-stubborn-dog-containment-system-add-on-collar-receiver/ extremedogfence.com

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.