Take two 35mm film canisters and chop them down to length - you will find that they will fit quite well. (Not my own idea - I saw this on the web somewhere else...)

By John on Monday, October 04, 2004 - 04:45 pm:

I have a couple of TLR lenses that are missing the caps that cover the body side of the lens (ie the ones that have to be removed before fitting the lens to the camera, not the ones that stay on the lens until you want to take the picture). can anyone recommend a source for these or have some to sell? Thanks