The DDC-50 Screw-Knob Clamp from Sunwayfoto is a standard length screw-knob, captive design clamp that's compatible with Arca-style QR plates. It mounts with a flathead screw from above--the ball post accepts an M6 screw and the clamp is 3/8" threaded. This clamp will mount to Sunwayfoto ballhead DB-44(LR) and Arca-Swiss RRS ballheads. It has safety stop relief grooves and a spirit level.
- Compatible with Arca-style QR plates