The 2 inch Brass SPG is for the beginner or the most advanced technical divers. The Hollis 2 inch Brass SPG Comes with a Luminescent face plate with an operating range of 0 to 5000 PSI or even an option for 0 to 360 BAR. The Hollis 2 inch Brass SPG has a chrome plated brass housing and uses a bourdon tube for calibration and accuracy. Equipped with scratch resistant glass. The Hollis 2 inch Brass SPG is oxygen cleaned for use of pure Oxygen or specialty blends for stage and deco bottles or just plain old Nitrox mixes. This gauge is sold separately and does not include a HP hose.