Tape cassette having ribs and window

摘要

A tape cassette comprising a cassette casing composed of an upper half casing and a lower half casing, a pair of hubs around which a magnetic tape is wound and which are rotatably fitted into circular peripheral walls formed in the cassette casing, and tape guide members formed in the cassette casing at positions through which the magnetic tape wound around the hubs is traveled, wherein the thickness of the flat surface walls and the thickness of the outer peripheral walls of the upper and lower half casings are respectively uniform.