Machined from a single piece of 6061 aluminum, this Global Dynamics United Canon Lens Port Cap is anodized red for wear resistance and a striking finish and relieved to reduce weight. The knurled edge provides a non-slip grip for handling. The front of the cap overs the front of your mount, protecting not just your camera's internal components, but also the lens port itself. Engraved markings on the front of the cap identify the correct mounting orientation.