Yes, and no. Later K-mounts have electrical contacts, and there are caps that have a lip that protects those contacts. In any case, buying less expensive PK caps from third party suppliers can sometimes be an issue as they may not always fit very well. So, all caps for K-mount lenses will fit. Some (like genuine Pentax caps) may fit better, and some, like the later Pentax caps, offer greater protection.
FWIW, I've pretty much switched to the later style Pentax caps even though my lenses don't have electrical contacts. The caps with the lips keep the dirt and grime off the lens mounts better. Shel > [Original Message] > From: Isaac > Hello, I was wondering if anyone could direct me to a source for rear lens > caps. My local camera shops don't have any. This is probably a stupid > question, but do all the K mount lenses use the same rear cap? I would think > so just because they would need the same hook up to mate with the camera. At > least that is my reasoning.
