Nikon Series E 28mm f2.8 projector 3/8” threads on top and

3/8” threads on top and bottom for leg and head connection

but you can still see it if you angle it to the light just so

This extension tube set includes two M42 thread-mount extension tubes: roughly 7mm and 15mm

ideal for push processing

A convenient zoom range in a lightweight package

Nikon Series E 28mm f2.8 projector 3/8” threads on top andThe Nikon Series E 28mm f2. 8 is a very compact wide angle lens for Nikon F mount. Series E lenses are Nikon's "cheaper" manual focus lenses, usually with older designs this one's based on the pre AI 28mm and more lightweight construction. Not a bad little lens, though! Light dust, smooth focusing, excellent cosmetic condition.