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MS21045-5

Military Standard Locking Hexagon Nut Self

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Description

Nut

Specifications

Alternate Part Number 404-889
Bearing Surface Finish 125.0 microinches, 125.0 µin
Bearing Surface Type Chamfered Faced, Chamfered or washer faced
Countersink Angle 88.0 degrees nut
Features Regular Height
Industry Standards/Certification MS21045
Locking Feature Prevailing Torque All Metal Design
Lubricant Non-Dry Lubricant
Lubrication Soluble Lubricant
Material Steel
Maximum Dimension A 0.360 in
Maximum Dimension B 0.502 in
Maximum Nut Height 0.360 in
Maximum Width Across Flats 0.502 in
Minimum Dimension A 0.271 in
Minimum Dimension B 0.492 in
Minimum Dimension C 0.552 in
Minimum Dimension F 0.123 in
Minimum Nut Height 0.271 in
Minimum Width Across Flats 0.492 in
NIIN 00-982-4912
NSN 5310-00-982-4912
Nominal Countersunk Angle (Nut) 88.0 º
Nominal Temperature Rating 450.0 ºF
Nominal Thread Size 0.312 in
Nut Height Between 0.271 inches and 0.360 inches
Nut Style Hexagon
Service Temperature 450 ºF
Surface Treatment Cadmium and chromate
Surface Treatment Document and Classification QQ-P-416,TY 2,CL 3 FED SPEC Single Treatment Response
Surface Treatment Specification Cl 3 federal specification single treatment response type 2 qq-p-416
Temperature Rating 450.0 degrees fahrenheit
Thread Class 3b
Thread Direction Right-hand
Thread MIL-S-8879 0.3125-24
Thread Qty 24
Thread Qty Per Inch (tpi) 24
Thread Quantity per Inch 24
Thread Series Unjf (fine thread with external controlled root radius)
Thread Size 0.312, 5/16-24
Type Self-Locking Nut
Weight 0.0118 lb
Width Across Flats Between 0.492 inches and 0.502 inches

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