ELI5: Explain Like I'm 5

Lens cover

A lens cover is like a hat for your camera lens. Just like how we wear hats to protect our heads from the sun or rain, camera lenses wear lens covers to protect them from dirt, scratches, and other things that can damage them. The lens cover sits on top of the lens and can be taken off when you want to take a picture. It is important to put the lens cover back on when you are done taking pictures so that the lens stays clean and protected.
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