C4 sunglasses have been specifically designed for the use at sea.
 
On the inside of the frame they feature a sponge, made of floating and water-repellent material, that allows them to be easily recovered on the surface, in case of an accidental drop in the water.
 
The glasses have polarized mirrored lenses ideal for the use on a boat. They feature detachable arms and an elastic strap and they are sold in a rigid EVA box with a lens cleaning cloth.