Appleton® UNILETS® Conduit Outlet Box, T-Style Dust-Ignitionproof Explosionproof, Series: GR Series, 1/2 in, 3.38 in Cover Opening Size, 18 cu-in, For Use With: Threaded Metallic Conduit System, Malleable Iron, Triple Coated, 3-3/4 in H x 3-3/4 in W x 2-1/4 in D