This is the XS Scuba ScubaPro Style QD Adapter Features: Convert any standard regulator hose to a ScubaPro Style" QD hose Installs to the second stage end of a regulator hose Chromed brass construction with Viton o-rings Low pressure use only - below 200 psi Compatible with: ScubaPro Air 2, Tusa Duo Air, Atomic SS1, Sherwood Gemini, Zeagle Octo-Z XS Scuba&';s QD Adapters allow you to convert any standard regulator hose to a Scubapro style QD hose. QD Adapter is a must item for your save-a-dive-kit and can quickly save an expensive dive vacation problem. "