LensCoatA(R) for the Canon RF 800mm f11 IS STM LensCoatA(R) telephoto lens covers offers your valuable equipment some protection from scrapes and bumps, preserving its resale value. It also help break up the shape of your lens, making it less noticeable to wildlife. The neoprene LensCoat acts as a thermal barrier making the lens more comfortable to handle in hot and cold tempertures. The LensCoatA(R) 800 RF features a clear plastic windows over the auto focus and Image Stabilization controls. *This cover comes with an optional piece for the lens barrel is extented which can be quickly and easily put on and removed with its Velcro attachment as seen in the picture.