WonderPana FreeArc XL Essential ND32 0.9 Soft Edge Kit for Canon EF 11-24mm f/4L USM Lens (Full Frame 35mm) Free Arc rotates filter at any angle: mount 1 round & 1 square filter, or 2 square filters simultaneously Ultra wide angle construction to eliminate vignette, All metal build - two component collar system for secure mounting Doubles as a hood to help protect your lens from damage, scratches, fingerprints and the elements Kit Includes: Free Arc XL Core Unit, 186mm Lens Cap, WP80 Filter Brackets, 186mm ND32 Filter and 0.9 Soft Edge WP80 Filter 24-Month Manufacturer Warranty