Hejnar FS-635 Quick Release Clamp – 2.375" Arca-Swiss with M8 Thread for Slik PBH-635AS. Markins, Really Right Stuff (RRS), Arca Swiss. Need bundled Arca plates or alternate thread sizes?. The center hole is threaded for M8, and the clamp includes2.6mm deep relief grooves to support safety-stop-equipped plates and prevent free fall when not fully closed.
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