Features Adjustable Diameter Range: Features an inner diameter adjustment from 1.5mm to 25mm, allowing you to customize light transmission for various optical needs Effortless : The intuitive handle design makes it easy to adjust the aperture diaphr diameter quickly and ly, enhancing user experience during setup Construction: Crafted from high-quality aluminum alloy and stainless steel, this diaphr ensures long-lasting performance and reliability in demanding environments Features: 1、1.5mm to 25mm: The aperture has an outer diameter of 55mm and an adjustable inner diameter of 1.5mm to 25mm, which provides small holes with different in the optical system to meet different light transmission requirements. 2、Simple : Just use the handle to change the aperture diaphr diameter, which is easy to operate and more directly for adjustment. 3、Reliable Materials: The aperture diaphr is made of aluminum alloy and stainless steel, strong and sturdy, very reliable in performance. 4、Highly Stable: This diaphr is light weight, will not add extra weight for optical systems, with high strength, and resistance, very stable. 5、Wide Application: This adjustable aperture diaphr is suitable for cameras, microscopes and other machines, which can help them work better. Specification: Item Type: Iris Diaphr Material: Alumnium alloy, stainless steel. Product Inner Hole Diameter: Approx. 1.5 ~ 25mm / 0.06 ~ 0.98in product Outer Hole Diameter: Approx. 55mm / 2.17in Product thickness: Approx. 17.5mm / 0.69in Blades: 14pcs blade. Product Thread: M42 to M42 Package List: 1 x Iris Diaphr Package List 1 x Iris Diaphragm