The Cullmann Magnesit MX492 Sliding Quick-Release Plate - 2.56" Long is a cast-aluminum quick-release plate that features Arca-Swiss-style grooves for attachment to a compatible quick-release assembly. By sliding the plate forward and back in the clamp, you can achieve proper balance for your camera. The plate has two camera-fixing pins for increased camera stability in portrait mode, as well as mounting for Cullmann"s CX678 bubble level. A flip-up thumbscrew enables tight fastening of the plate to the camera. A metric ruler on the side facilitates precise adjustments.