Magnetic tape cassette

摘要

A magnetic tape cassette comprises an upper half casing and a lower half casing provided with a screw holder having a threaded hole at the corner of the lower half casing for connecting said upper half casing, wherein the thickness of the wall of the screw holder facing inside the casing is reduced and at least one rib having a level flush with the fitting surface of the lower half casing is formed at the inside portion of the screw holder.