View the peephole from the interior side of the door.
Grasp the ring around the scope of the peephole on the interior side.
Turn the ring counterclockwise by hand to unscrew it. You may need to hold onto the peephole from the door’s exterior to ensure it does not fall out of the door. If you cannot unscrew it by hand, use a wrench.
Pull the inner scope out from the interior side of the door once it's unscrewed.
Pull the outer scope from the exterior side of the door.