The Pentax K Rear Lens Cap protects the back of the camera lens from scratches and dirt.
Pentax K Rear Lens Cap
The Pentax K Rear Lens Cap twists into the back of the camera lens when not in use, to protect the rear of the camera lens from scratches, smudges and dirt.
Simply remove the camera lens from the Pentax K camera body and then twist the rear lens cap in to the back of the lens.