1 -5/8" (42mm) steel dial Groz pressure gauge is a threaded back mount gauge type. Brass internal construction with clear glass front lens. Accuracy within 5% temperature range 32å¡ ‰ÛÒ 140å¡ F (0å¡-60å¡c) 1/8" NPT male threads on the back center and fit female threads on the regulator. 1/8" thread size fits miniature, intermediate, standard Groz regulators. A2G14.