Characteristic: 1. In the optical system there are small holes of different diameters to meet different requirements for light transmission. 2. Change the diameter of the hole at the handle. 3. Metallic material, reliable performance, durable. 4. The compact and practical design makes the membrane work more stable. . MICROSCOPE APERTURE ADJUSTABLE SK25 Specification: Item Type: SK25: Enlarged diameter: 1,5-25 mm Material: Metal Outside diameter: 44mm Inner diameter: 25mm Thickness: 8mm 14 blades SK23 Outside Diameter: 37mm Minimum hole diameter: ø1,5 mm Maximum hole diameter: ø23mm Material: metal Thickness: 7,0 mm 12 blades SK12 Outside diameter: 19,8 mm Minimum aperture: ø1mm Maximum aperture: ø12mm Material: Metal Thickness: 5,0 mm 10 blades SK8 Outside diameter: 14,8 mm Minimum aperture: ø0,8 mm Maximum aperture: ø8mm Material: Metal Thickness: 4,5 mm 8 blades SK6 Outside diameter: 13,0 mm Minimum aperture: ø0,8 mm Maximum aperture: ø6mm Material: Metal Thickness: 6mm 8 blades . MICROSCOPE APERTURE ADJUSTABLE SK25 List of packages: 1 x Membrane . MICROSCOPE APERTURE ADJUSTABLE SK25 . MICROSCOPE APERTURE ADJUSTABLE SK25