This Lens Cover by LensCoat is specifically designed for the Olympus M.
Zuiko Digital ED 150-400 mm f4.
5 TC1.
25x IS Pro Lens.
It protects the lens from scratches, minor impact, and comes in a RealTree 4 Max pattern.
It provides a thermal barrier in cold weather conditions, keeping your hands warm and provides full functionality with a variety of features.