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Koolertron DSLR/VCR Shoulder Mount Rig Follow Focus Matte Box 15mm C-Shape Support Mount

Make You Shoot Or Video Production Steady Precise And Smooth
14 Screw Head Compatible With Most DSLRVCR
Matte Box Compatible With 15mm Rail Road Support System
Material Aluminum alloy
Gears Nylon And ABS Dial Index Adjustment 360