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MS21900D4

Military Standard Boss Nipple

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Description

Boss Nipple

Specifications

Connection Style External seat for gasket seal (boss) 2nd end, Flared w/ gasket seal (boss) 1st end
Connection Type Threaded external boss all ends
Material Aluminum
Nominallength 1.188
Specification Data 96906-ms21900 government standard
Style Designator Flared and flareless w/ center wrenching facility
Surface Treatment Anodize
Thread Class 3a all ends
Thread Series Designator Unjf all ends
Thread Size 0.438 inches all ends

Other sizes

Parts that share this base number, ordered by size. Always verify the full specification before substituting.

Cross-reference

Interchangeable

Parts that share a National Stock Number or are listed as an alternate for MS21900D4 — functionally equivalent.

  • MS21900W4 Listed alternate 7/16 in · Aluminum

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Catalog data updated 2026-07-05. Report a data error