Item Type: 244mm Adjustable Iris Aperture Weight: 46g/1.6oz Material: Aluminum alloy Hole Diameter: 2mm-44mm Package List 1 x Adjustable Iris Aperture 1 x Packaging Box 12mm to 44mm Adjustable: Adjustable hole inner diameter 244mm, outer diameter is 60mm, thickness of 6mm, 16 blades, in the optical system to provide different diameter holes to meet different light needs. 2Simple Operation: Just rotate the outer ring to change the aperture diameter, simple operation, direct adjustment. The compact and practical design makes the diaphragm a more practical way of working. 3Highly Stable: The diaphragm is lightweight, does not add extra weight to the optical system, high strength, rustproof, and very stable. 4Wide Range of Applications: This adjustable aperture is suitable for cameras, microscopes and other machines, which can help them work better. 5Reliable Aluminum Alloy Material: Aluminum alloy material, strong and durable, very reliable performance, long service life.