Genuine Dell Studio 1555 1535 Series Laptop CD/DVD±RW SATA Burner Optical Drive AD-7640S WT897 0WT897 CN-0WT897.Model Number: AD-7640SDell Part Number: WT897 0WT897 CN-0WT897Compatible Part Numbers: SOK-AD-7640S(B) 0731371-000Compatible Models: Dell Studio 1555 1535 Series