Helps protect the surface of The MK1 Lens (a.k.a. The Death Lens / The Mark 1 Lens / Century Precision Optics DS-FEWA-00 0.3x Ultra Fisheye Adapter Lens).
- 100% unobstructed field of view (No vignetting)
- Straightforward design and easy to attach
- Outside (convex side) coated with scratch resistant military grade hard coating