Tested, certified, error free and 100% guaranteed against manufacturer's defects. Liability limited to refund or replacement. Details enclosed. Conforms to ANSI stands. Product Specifications: 135 Tracks per inch, 80 Tracks per side, Double Sided/ High Density Product Compatibility: Pre-formatted for use on all IBM compatible computers. can be reformatted for use on any 3.5" double sided, high density, floppy disk drive.