Crouse-Hinds series EMH explosionproof instrument housings are used to enclose 2-1/2" or 3-1/2" diameter round, flush rim-mounting meters, whose scale or dial would be visible in the 2-5/8" diameter glass window. EMH instrument housings are certified for use in Class I, Division 1 and Class II, Division 1 areas. They are commonly used in oil refineries, chemical plants, paint and varnish manufacturing plants, coal processing locations, grain processing plants, and other industries with explosive gases or dusts.