The 2" GK53 and 2½" GK54 gauges are all stainless steel. The are factory cleaned for oxygen service and have become the gauge of choice for many of America's top regulator manufacturers. These gauges have a ¼" bottom stem connection, a polished stainless steel case, stainless movement, and a one piece polycarbonate bezel and lens.
The gauges are designed for rugged service with built-in mechanical stops. Zero pins, which can trap a pointer and cause a gauge to lose calibration are not used.