Size: 2.50" Tube DiameterBillet machined bar mounts make it easy to mount intercoms, headset hangers, and other accessories to 2.50" diameter tubing. 2.50" Tube Diameter Half-Clamp Design Stainless Steel Hardware CNC machined alloy Black anodized finish A hole in the bottom of mount accepts an 8-32 screw. The screw is not included.