Black nylon plastic with a matte finish and slight grainy feel.
About this Product
While the 37mm filter holder alone works great for macro lens, for ND filters in direct sunlight, the sun hood really helps get the best image. The sun hood and 37mm filters works fine for all Medium and Narrow fields of view on the GoPro HERO3, HERO3+ & HERO4 cameras. As it is difficult to 3D print fine filter threads, this is just a fiction fit.
Note: This is not an official accessory, use on your GoPro at your own risk.