Feature: 1. This iris diaphragm is exquisite and smooth, anti-corrosion and durable for a long time 2. The product is made with independent development, come with high accuracy, you can use with confidence 3. Made of good-quality materials, no burrs or pressure points, and no deformation of the product 4. This is an indispensable accessory for laser, camera and optical platform, very practical 5. The product can provide different straight holes in the optical system to meet different light requirements, the diaphragm diameter can be changed by adjusting the handle Specification: Item Type: Iris Diaphragm Model: SK12 Material: Iron Uses: Accessories for lasers, cameras, and optical platforms Enlarged Diameter: Approx. 1 ~ 12mm / 0 ~ 0.5in Outer Circle: Approx. 19mm / 0.7in Inner Hole: Approx. 12mm / 0.5in Thickness: Approx. 5mm / 0.2in. Package List: 1 x Iris Diaphragm