Four cable knockouts (sides). Two 1/2 in and one eccentric TKO conduit knockout (sides). One 1/2 in conduit knockout (bottom). 2-1/8 in D. 30.3 cu-in. With clamps for non-metallic sheathed cable. TS, flush side-mount bracket for wood or metal studs. Fixture support of 6 lb maximum. Acceptable for use in 2 hrs rated fire walls. UL listed.