LensCoatA(R) for the Canon EF 16-35mm f/4L IS LensCoatA(R) EF 16-35mm f/4L IS lens cover offers your valuable equipment some protection from scrapes and bumps, preserving its resale value. It also helps break up the shape of your lens, making it less noticeable to wildlife. The LensCoatA(R) EF 16-35mm f/4L IS features a clear plastic windows over the auto focus and focus limiter switch and also the distance scale.