Fotodiox M39/L39 Metalen Achterlensdop - Zilveren Beschermende Achterdop voor 39mm Schroefdraad Camera Lenzen

Finally found a rear cap that won't crack after a few months of pocket carry—this one's metal and has that satisfying thread-on click. Keeps the dust out of my M39 lenses when they're sitting on the shelf, and the silver finish matches my gear nicely.

The metal build feels reassuringly solid compared to the flimsy plastic caps I've used before, and the anti-rust finish is a nice touch for humid climates. It screws on smoothly and sits flush, so I don't worry about it popping off in my bag.

Exactly what I needed for my old screw-mount lenses—the silver finish matches perfectly and the threads screw on smoothly without any wobble. The metal construction feels substantial and should protect the rear element for years to come.