This is the XS Scuba Tank Muffler For Scuba Diving DIN or Yoke Valves Features: Drain it quietly, drain it slowly, drain it safely Attach to DIN or Yoke style valves Exhaust holes on opposite side of XS Scuba logo All brass construction The XS Scuba Tank Muffler Valve is the perfect solution for keeping noise levels down while draining your tank. It securely attaches to both DIN and Yoke style valves, and features exhaust holes on the opposite side of the XS Scuba logo. Constructed with all brass, this muffler allows you to confidently and safely drain your tank.