Retention Ring for Fotodiox M42 Type 1 Lens Mount Adapter - Easily Adapts Type 1 M42 Adapters into Type 2

Fotodiox

Features: Metal Construction, Crush Resistant, Anti-Rust, Solid & Durable Provides a 'Shelf' for the Lens Iris Lever to Press Against Turns a Type1 Adapter into a Type2 Limited 2-Year Manufacturer Warranty This insert is designed to fit inside of M42 lens mount adapters, this provides a 'shelf' for the m42 lens aperture lever to press against which in turn activates the lens iris control, effectively turning a Type 1 adapter into a Type 2. Mount Type 42mm x1 (M42) Screw Mount Camera Lens Materia