When you need to empty a cylinder for visual inspections, transporting for travel or when valve maintenance is required you need a tank muffler. Tired of the overbearingly loud and high-pitched sounds of draining a Scuba tank? The sound of a draining Scuba cylinder can cause hearing damage if not done properly. Draining the cylinder at a rate that won't offend your hearing can take hours. To easily drain a cylinder at a functional and less time consuming rate than the XS Scuba Tank Muffler is just what you need. Quiet, slow, safe tank draining. Compatible with DIN or Yoke valves and constructed with marine grade brass for durability and corrosion resistance. The exhaust holes are opposite from the XS Scuba logo.