Pentax Auto 110 lens set (50, 24 and 18mm) monitor Nikon BR-3 adapter ring

Nikon BR-3 adapter ring

but the long rear flange will interfere with full-frame SLR mirrors- so keep it away from your 5D

It doesn't affect imaging and it's not going to get any worse

and good diaphragm action (with slight wear on the blades)

Pentax Auto 110 lens set (50, 24 and 18mm) monitor Nikon BR-3 adapter ringA set of three lenses for the Pentax Auto 110 SLR system. This outfit includes a wide angle 18mm lens, a "standard" 24mm lens, and a 50mm short telephoto lens, all f2. 8. All three are in good cosmetic condition, with minimal signs of wear. The glass of the 24mm and 50mm are in good shape; the 18mm has a touch of haze. Good quality lenses with smooth focusing. Can be adapted to Pentax Q system or Micro Four Thirds cameras (adapters not included).