Genuine Cressi O-Ring + Screws replacement for the Cressi watch-style dive computers only. Compatible with any watch-style dive computer. Models: Drake, Newton, Cartesio, Goa, Neon, King, Nepto. The kit is composed of the O-ring and the pair of little screws with nylon washer for the battery cover. The battery is excluded. It is recommended to proceed carefully with changing the battery and the O-ring. In case of trouble, it is suggested to contact an authorized service center to change the battery. The Cressi Authorized Dealers are listed on the official Cressi website.