Brand New Aluminum NW/KF-16,KF-25,KF-40,KF-50 Quick Clamps Easy to clamp and secure tight. A circumferential clamp and centering ring form the vacuum seal between the connecting flanges. This clamp is used for connecting standard NW/KF-16,KF-25,KF-40,KF-50 vacuum components. Made of High Quality Aluminum so it will not bend & ensure a tight fit. Aluminum Wing Nut Flange Quick Clamp for Degassing Chamber, Vacuum Oven, Vent Lines, etc.