The MH667 Quick-Release Clamp with MH667Q QR Plate from Giottos allows you to attach an Arca-type compatible clamp to any support with a 1/4"-20 stud. The system includes the clamp and the MH665Q plate. A vertical bubble level is incorporated within the adapter's locking knob, and a horizontal bubble level is positioned on the base of the adapter. The 2.76" long plate features rubber grips and a camera screw, which has a semi-circular tightening wing around it. It lets you lock down and orient your camera in the desired position before attaching the plate to the adapter base.