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LensCoat LC400282M4 Canon 400 f/2.8 IS II Lens Cover (Realtree Max4 HD)

Protection from bumps dings nicks and the elements like water sand dust etc
Camoflauge patterns help conceal by breaking up the shape of the lens
Neoprene acts as a thermal barrier protecting hands from hot and cold
Slides on like a sleeve
Made in the USA