Stub ends come in three different types, named "Type A", "Type B" and "Type C". Type a and B are manufactured with cast or forged materials. The first type (A) is manufactured and machined to match standard lap joint backing flange (the two products have to be used in combination). The mating surfaces have an identical profile to permit a smooth loading of the flare face. Stub ends type B are have to be used with standard slip-on flanges. Type C stub ends can be used either with lap joint or slip on flanges and are manufactured from pipes. The most widely diffused type of fabrication is with a flare machine, which flares the end of the pipe and then cuts it to length. Stub ends are available in two different patterns, the short (used with larger flanges for ASME 300# and 600#) and the long type (known as ASA stub ends, used for most sizes from class 900 & above).