LensCoatA(R) for the Canon RF 100-300 f2.8 L IS USM 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. LensCoatA(R) for the Canon RF 100-300 f2.8 L IS USM features a clear plastic window over the auto focus/IS controls.