The Sirui PH-120 Quick Release Plate is made from forged aluminum alloy. The forging technique produces high-density metals with much greater strength than die-cast methods. This PH-120 is designed with slide-stopping rubber mats to prevent the camera/lens from moving while tightening the screw and it is Arca-compatible. The red anti-twist stoppers is designed to prevent the camera from shifting or twisting as you move the ball head. And the Special QR Plates are model specific for a perfect fit.