Yoke (A-clamp) tank valve

A yoke valve is a tank connection that uses a metal frame to clamp against the regulator. This design is often called an A-clamp because of its shape. Most rental tanks in Koh Tao or Cebu use this style since it is cheap and simple. You will see these on almost every standard aluminum 80 tank.

Check the O-ring. Always inspect the small rubber ring on the regulator first because a dry seal causes massive air leaks during your dive. I once lost 30 bar in ten minutes because I forgot this step in Anilao. If you hear a hiss, tighten the yoke knob slowly. Do not over-tighten it. Over-tightening can damage the threads or the tank neck itself. Most divers prefer DIN valves for technical diving, but yokes remain the standard for recreational trips.