Piston Gauge A piston gauge, located at the 102nd Precision Measurement Equipment Laboratory, Otis Air National Guard Base, Mass. The 102nd Precision Measurement Equipment Laboratory provides precision calibration and measurement for nine different Air Force and Air National Guard flying missions, as well as support for Coast Guard District 1. SHARE: Download: Full Size (1.14 MB) Credit: Air Force Master Sgt. Kerri Spero, Massachusetts Air National Guard VIRIN: 200501-Z-OD508-0008C.JPG Photo Gallery