SMC Pentax-F 50mm f/1.7 Filter Type_Infrared or pull off the top

or pull off the top cover and use only the bottom half case

full compatible with any Nikon AF or AF-D lens

there's a pretty decent chance that the mark has existed since this lens left the factory

Really wide

with minor cosmetic wear from normal use

SMC Pentax-F 50mm f/1.7 Filter Type_Infrared or pull off the topThe SMC Pentax F 50mm f 1. 7 is a compact standard lens for Pentax K mount cameras, with autofocus linkage for cameras with focus motors in the body. Naturally, this lens can also be focused manually on older K mount cameras. In excellent condition, with minor cosmetic wear, smooth focusing, good diaphragm action, and clean glass bar some minor coating marks on the front element.