Canon ERC-E4S is a rain cover for compact DSLR camera setups (including the lens). The cover keeps the professional camera dry when shooting in wet conditions, and the transparent window provides a clear view of the top and rear LCD panels. The front closure opens easily, so removing the lens from the camera is not a problem. Size S is suitable for lenses such as Canon EF 100–400 f/4.5–5.6L IS USM, Canon EF 28–300 f/3.5–5.6L IS USM, Canon EF 300 f/4L IS USM, and others.