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MS21043-5

Name: MS21043-5
Brand: MS
SKU: MS21043-5

Military Standard Locking Extended Washer Nut Self

Description

Nut

Alternate Part Number	NAS1022C5
Features	Heat Resistant
Finish	Silver Plate
Industry Standards/Certification	MS21043
Locking Feature	Prevailing torque all metal design
Lubrication	Soluble lubricant
Material	CRES
Material Specification	Ams 5525 assn standard single material response or ams 5735 assn standard single material response
Maximum Diameter A	0.520 in
Maximum Dimension H	0.266 in
Maximum Dimension W	0.378 in
Minimum Dimension C	0.419 in
Minimum Dimension H	0.251 in
Minimum Dimension W	0.367 in
NIIN	00-881-0944
NSN	5310-00-881-0944
Nut Style	Hexagon
Overall Height	Between 0.251 inches and 0.266 inches
Precious Material And Location	External surface silver
Service Temperature	800 ºF
Shape	Reduced Hexagon
Surface Treatment	Silver
Surface Treatment Specification	Qq-s-365 federal specification single treatment response or ams 2410 assn standard single treatment response
Temperature Rating	800 degrees fahrenheit
Thread	5/16-24
Thread Class	3b
Thread Direction	Right-hand
Thread Qty	24
Thread Qty Per Inch (tpi)	24
Thread Series	Unjf (fine thread with external controlled root radius)
Thread Size	0.312, 5/16-24
Type	Self-Locking Nut
Washer Outside Diameter	0.520
Washer Thickness	0.023
Weight	.005 lb
Width Across Flats	Between 0.367 inches and 0.378 inches

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

Parts that share a National Stock Number or are listed as an alternate for MS21043-5 — functionally equivalent.

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