Abstract: A cassette Jacket for a 3.5" diskette comprising a front plate, rear plate, two fixed-side leaf springs, and a bottom plate. The front plate covers the read/write sector opening of the diskette. The rear plate covers the center opening and the read/write sector opening of the diskette. A retainer located on each leaf spring is received in an opening located in each side of the cassette to fix the Jacket on the cassette.