Made of aluminum alloy, Slim and durable Great for storing and carrying filters Protects your filters from dust, scratches and fingerprints Enables streamlined system of organizing filters 6mm slim filter stack cap Filter case protect filters from dust and scratches while they are not being used^ Simply screw the filters together, then screw these stack caps on the top and bottom.^ Compatible to lens with 82mm thread size, and 82mm Filters^ Material: aluminum