Adapter, Straight Reducer, KF-40 to ISO-63 Large Flange, Flange Size ISO-KF NW-40 to ISO-LF NW-63, Stainless Steel
 
These adapters are KF-40 to ISO-63 large flange (LF). The flange size follows ISO standards and are NW-40 to NW-63. They are commonly used to make connections between ISO-KF and ISO-LF fittings. The ISO-KF flanges 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 corrosive resistant stainless steel.

Adapter KF-40 to ISO-63 Large Flange, Flange Size ISO-KF NW-40 to NW-63, Stainless Steel
Flange Size: ISO-KF NW-40 to ISO-LF NW-63
Common Dimensions: A = 1.77" (45mm), B = 1.37" (35mm)

Adapter KF-25 to ISO-63 Large Flange, Flange Size ISO-KF NW-25 to NW-63, Stainless Steel
Flange Size: ISO-KF NW-25 to ISO-LF NW-63
Common Dimensions: A = 1.77" (45mm), B = 1.00" (26mm)