Pentax X Mount Lens Cap
Related Faq
Q
Q: Is it possible to attach a filter cap to this filter? How should I choose?
A
Answer: you can install the lens cap, the same diameter can be 
Q
What size lens cap would I need for the 58mm ND2-ND32 (1-5 Stop) Variable ND Filter and CPL?
A
hi,please choose 67mm lens cap. 
Q
Will this work with the pentax mount asahi takumar smc 50mm 1.4?
A
Yes. I have the same lens and adaptor on my Sony a7ll and it works beautifully. The m42 is also known as the 'universal' mount as other 3rd party camera and lenses also used it. I own 6 other K&F e-mount adaptors to different lens makers (ltm, MD, CF/CD, Nikon) and they all are well built with a nice snug fit. Highly recommended. 
Q
Pentax pk mount usually means pentax k mount which has a flange distance greater than m. is this adapter for adapting leica m lens to pentax q camera?
A
I actually have not received this adapter yet. It's shipping from China. Don't think that was disclosed in the ad. However, I do not believe this is for the Pentax Q body rather for digital and film cameras that take the Pentax K mount in its many variations. So I'm expecting to be able to mount my Leica M mount lenses on my digital and film Pentax K mount cameras, no autofocus or relay of exposure information, only to be used with manual focus and exposure. 
Q
Can this filter be fitted with a lens filter cap? How should I choose?
A
Same caliber can be installed the lens cap 
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