Set of three optical drive mounting brackets plus screws for all PowerBook G4 15" models. The set comprises the left, front and right hand brackets, the 4 drive screws (2 for the left and right bracket to fix them onto the optical drive), the 2 right hand bracket mounting screws which fix the whole unit into the PowerBook G4 chassis, and 3 to hold the front clamping bar in place. It is not supplied with the left hand bracket mounting screws as the this bracket is secured by the hard drive mount screws. It is important that the screws are used in the correct position. Please refer to the photo which shows each screw next to where it should go.