HANGARBIBLE
Aviation HUBStudy and reference guide

FIND CLAMPS

Loop size, band and cushion by part number

Which standards this page can answer for
StandardRowsWhat it is
MS21919 / AS21919768The cushioned loop clamp of every hangar. One bolt hole, a metal band and a bonded cushion. The dash number is the loop bore in sixteenths of an inch, so −8 is 1/2". AS21919 is the same clamp under the SAE number that replaced the MS sheet.
ABS1339 / CC133932The light clamp, plastic bodied and sized by the bundle range rather than by a bore. CC1339 is the Amphenol equivalent, about 18% lighter, and the catalogue lists it as replacing ABS1339.
MS21333 / NASM21333129The other loop clamp of the MS world, published plain and cushioned: the standard lists a plain dash and a cushioned dash against each loop size, so MS21333-13 and MS21333-77 are the same 1″ loop, bare band and cushioned band. Suffix A is the thinner 0.032 in plastisol cushion. Sizes run 0.125″ to 4″.
NSA935401 / EN242446Stainless P-clamp with a silicone cushion, rated to 260 °C and used where fuel or heat rules out the aluminium/chloroprene clamp.
AN74251The plain loop clamp, no cushion — the bare-band predecessor of MS21919. The dash is the tube diameter in sixteenths, so AN742D8 is 1/2"; D is aluminium alloy. From the Skybolt 2017 catalogue: 36 sizes printed there, 15 listed without a size and read from the dash.
AN737TW / MS3584229Worm-drive hose clamps, sized by an effective diameter range rather than one bore: the clamp fits any hose whose outside diameter falls inside it. From the Skybolt 2017 catalogue.

REFERENCE ONLY — not authorized for maintenance, repair or return-to-service. Dimensions are the catalogue figures for the part number, not a measurement of the clamp in your hand, and a clamp called out by a maintenance task or a parts catalogue figure is the one to fit. Band and cushion materials decide where a clamp may be used: a chloroprene cushion is a 100 °C part and does not belong in a hot or fuel-wetted zone.