Gray Ghost Amphibian Underwater Headphones, Minelab CTX 3030Gray Ghost Amphibian II Headphones incorporate a number of dramatic improvements in weatherproof submersible headphone design. It is intended to replace your manufacturer land headphones and after market waterproof headphones. Now you can use one set of headphones for both land and underwater. The design is 100% waterproof and totally submersible to a maximum of 200 feet! No compromise in sound quality or functionality. Plus! New internal design