Lightweight C-Mount EOS M Ring

Ultra-compact C-mount to EOS M adapter ring built for reliability and repeatability. Physical specs: 24 mm OD × 11 mm height × 28 g weight. Machined from single-piece 6061-T6 aluminum, then bead-blasted and anodised for uniform texture and durability. Designed specifically for the 18 mm flange focal distance of EF-M mount — achieves accurate infinity focus by accounting for the exact 0.474 mm offset relative to C-mount’s 17.526 mm baseline. Fully manual: no electronics, no power draw, no firmware dependency. Compatible with all screw-type C-mount lenses — including zooms, macro, and varifocal models — provided they meet standard thread specification (1″-32 UN, 0.8 mm pitch). Not suitable for CS-mount lenses without additional spacers.