This is the Hollis Angle Adapter for Scuba Diving Second Stage Regulator Features: Increase Comfort and Reduce Jaw Fatigue Reduces Pulling Feeling" Installs to Second Stage end of Regulator Hose Allows Hose to be Routed-Comfortably and Streamlined in any Orientation Run-the-Hose Under-your-Arm for Back-Mount Straight-Down Chest to Bottle in Side-Mount Material: Chrome Plated Brass Factory-Cleaned Viton O-Rings Ready-for-Nitrox Out-of-the-Box Designed for Low-Pressure-Only 200 psi (13.8 bars) Does your regulator second stage feel uncomfortable in your mouth when diving? Does it feel like it is trying to pull out of your mouth when you turn your head? If these are problems, you have experienced when diving than you may need an angled adapter that can help eliminate this problem. Hollis Angled Adapter makes your primary second stage regulator more comfortable while you dive. The angle adapter allows your regulator hoses to be routed comfortably and streamlined in any orientation. Simply install between your low-pressure regulator hose and second stage regulator and run the hose under your arm for back-mount or straight down your chest to the bottle in side-mount. Angled adapter is constructed from chrome plated brass and is factory cleaned using Viton O-rings, so it's ready-for-Nitrox out-of-the-box. The Hollis Angled Adapter is designed for low-pressure only 200 psi (13.8 bars). "