These are Aluminum KF-10 Blank Flange fittings following ISO-KF standards and have a flange size of NW-10. They are commonly used to build foreline vacuum plumbing and process systems. They are often called quick flange fittings because they are quick to assemble. A circumferential clamp and centering ring form the vacuum seal between the connecting flanges (please see top right figure - click to enlarge). The centering ring contains a rubber elastomer o-ring. The standard sizes for quick flange fittings are KF-10, KF-16, KF-25, KF-40, and KF-50 with flange sizes NW-10, NW-16, NW-25, NW-40, and NW-50, respectively. They are made of ALUMINUM. Blank Flange ISO-KF Flange Size: NW-10

These Aluminum KF-16 Blank Flange fittings follow ISO-KF standards and have a flange size of NW-16. They are commonly used to build foreline vacuum plumbing and process systems. They are often called quick flange fittings because they are quick to assemble. A circumferential clamp and centering ring form the vacuum seal between the connecting flanges (please see top right figure - click to enlarge). The centering ring contains a rubber elastomer o-ring. The standard sizes for quick flange fittings are KF-10, KF-16, KF-25, KF-40, and KF-50 with flange sizes NW-10, NW-16, NW-25, NW-40, and NW-50, respectively. They are made of ALUMINUM. Blank Flange ISO-KF Flange Size: NW-16

These KF-25 Blank Flange fittings follow ISO-KF standards and have a flange size of NW-25. They are commonly used to build foreline vacuum plumbing and process systems. They are often called quick flange fittings because they are quick to assemble. A circumferential clamp and centering ring form the vacuum seal between the connecting flanges (please see top right figure - click to enlarge). The centering ring contains a rubber elastomer o-ring. The standard sizes for quick flange fittings are KF-10, KF-16, KF-25, KF-40, and KF-50 with flange sizes NW-10, NW-16, NW-25, NW-40, and NW-50, respectively. They are made of ALUMINUM. Blank Flange ISO-KF Flange Size: NW-25

These Aluminum KF-50 Blank Flange fittings follow ISO-KF standards and have a flange size of NW-40. They are commonly used to build foreline vacuum plumbing and process systems. They are often called quick flange fittings because they are quick to assemble. A circumferential clamp and centering ring form the vacuum seal between the connecting flanges (please see top right figure - click to enlarge). The centering ring contains a rubber elastomer o-ring. The standard sizes for quick flange fittings are KF-10, KF-16, KF-25, KF-40, and KF-50 with flange sizes NW-10, NW-16, NW-25, NW-40, and NW-50, respectively. They are made of ALUMINUM. Blank Flange ISO-KF Flange Size: NW-40

These Aluminum KF-50 Blank Flange fittings follow ISO-KF standards and have a flange size of NW-50. They are commonly used to build foreline vacuum plumbing and process systems. They are often called quick flange fittings because they are quick to assemble. A circumferential clamp and centering ring form the vacuum seal between the connecting flanges (please see top right figure - click to enlarge). The centering ring contains a rubber elastomer o-ring. The standard sizes for quick flange fittings are KF-10, KF-16, KF-25, KF-40, and KF-50 with flange sizes NW-10, NW-16, NW-25, NW-40, and NW-50, respectively. They are made of ALUMINUM. Blank Flange ISO-KF Flange Size: NW-50