Sony PlayStation 3 Super Slim Blu-ray Laser Lens KES-850A KEM-850 Deck For PS3 CECH-4xxx CECH-4000 CECH-4001A CECH-4001B Sony PlayStation 3 Super Slim Blu-ray Laser Lens KES-850A KEM-850 Deck For PS3 CECH-4xxx CECH-4000 CECH-4001A CECH-4001B Both models KEM-850PHA 4301B and KEM-850PHA 4301A are compatible and interchangeable.