Description: Adjustable Iris diaphragm series is used in the optical system, can provide different diameters to meet different requirements light. Adjusting the handle change the aperture diameter. High Quality: Using high quality iron material, anti corrosion, durable and reliable performance. Durable: without burrs and pressure points, product not deformed,exquisite and smooth. Wide Application:iris aperture adapter is very suitable optical applications, can be an accessory , camera, and optical platform. Specification: Aperture module integrated aperture manual adjustable variable aperture aperture adjuster zooms, in to out condenser 2.5-42MM Small holes with different diameters are provided in the optical system to meet different light transmission requirements. Use the handle change the diaphragm diameter. Metal material, sturdy and durable. Various common clear apertures. Model: SK42 Outer diameter: 58mm Minimum bore diameter: ø2.5mm Maximum bore diameter: ø42mm material: metal Thickness: 6.5mm Number of blade: 18 pieces Size Chart: Refer to the comparison table each type diaphragm Package Includes: 1x Iris Diaphragm(2.5-42mm)