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MS21900-4

Adapter

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Description

Adapter

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
Dimension E 0.688 in
Dimension N 1.188 in
Dimension S 0.563 in
Industry Standards/Certification MS21900
Material Steel
Material Specification Qq-s-637 federal specification single material response
Maximum Operating Pressure 3000 pounds per square inch single response
Maximum Operating Temp -65.0 degrees fahrenheit 2nd response, 275 degrees fahrenheit 1st response
Media For Which Designed Hydraulic fluid single response
NIIN 00-541-1579
NSN 4730-00-541-1579
Nominallength 1.188
Specification Data 96906-ms21900 government standard
Style Designator Flared and flareless with center wrenching facility
Surface Treatment Cadmium
Surface Treatment Specification Class 2 military specification single treatment response type 2 qq-p-416
Thread Class 3a all ends
Thread Series UNJF
Thread Series Designator Unjf (fine thread with external controlled root radius) all ends
Thread Size 0.438 inches all ends
Thread T 0.4375-20
Tube Outside Diameter 1/4 in
Weight 0.0043 lb

Other sizes

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

Cross-reference

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