LensCoat for the Canon 300 f/2.8 Black. LensCoat 300 telephoto lens cover offers your valuable equipment some protection from scrapes and bumps, preserving its resale value. The LensCoat 300 features a clear plastic windows over the auto focus controls, and also the distance scale. A small hole on the last segment lines up with the red dot indicator, making it easy to quickly line up your lens with camera mount even with the cover installed.