PartsTable
Technical Data Sheet
Download PDF

74638M624 — NUT,PLAIN,EXTENDED WASHER,DOUBLE

✓ Government record, cited
— · NUT WASHER
PRODUCT OVERVIEW

74638M624: NUT,PLAIN,EXTENDED WASHER,DOUBLE.

NUT,PLAIN,EXTENDED WASHER,DOUBLE. Key specifications include material: STEEL COMP 8740 OR STEEL OVERALL, nut_style: DOUBLE HEXAGON, temp_rating: 450.0 FAHRENHEIT MAXIMUM DEGF, thread_class: 3B, thread_series: UNIFIED NATIONAL JOINT FINE (UNJF), overall_height: 0.350 INCHES MAXIMUM IN. This part is cataloged in the U.S.

Government catalog under NSN 5310-01-059-0259, indicating validated use in U.S. government and defense logistics supply chains. Available through authorized enterprise resellers and TPM (Third Party Maintenance) channels.

Verify compatibility with your specific system configuration before ordering.

WHERE IT FITS
74638M624
NSN: 5310-01-059-0259
FSC: 5310 — Nuts and Washers
CAGE: 56878 — SPS TECHNOLOGIES, LLC DBA PB FASTENERS (USA)
SPECIFICATIONS
materialSTEEL COMP 8740 OR STEEL OVERALL
nut_styleDOUBLE HEXAGON
temp_rating450.0 FAHRENHEIT MAXIMUM DEGF
thread_class3B
thread_seriesUNIFIED NATIONAL JOINT FINE (UNJF)
overall_height0.350 INCHES MAXIMUM IN
hardness_rating44.0 ROCKWELL C MAXIMUM
special_featuresSLOTTED AND MOLYBDENUM DISULFIDE DRY FILM LUBRICANT AFTER PLATING
thread_directionRIGHT-HAND
washer_thickness0.065 INCHES MAXIMUM IN
surface_treatmentCADMIUM OVERALL
width_across_flats0.430 INCHES MINIMUM AND 0.439 INCHES MAXIMUM IN
NSN5310-01-059-0259
COMPONENT DIAGRAM
NUT & WASHER — GRADE MATCHING REQUIRED Hex NUT CROSS-SECTION WASHER OD: — SIZE: — MATERIAL: — PN: 74638M624 · OEM ⚠ VERIFY BEFORE ORDERING Grade matters for torque spec — don't mix grades. A Grade 5 nut on a Grade 8 bolt weakens the joint. Lock nuts, wing nuts, and castle nuts are NOT interchangeable with standard hex ✓ BROKER TIP Match nut to bolt thread class and material. Stainless bolt + zinc nut = galvanic corrosion. Always verify finish matches (plain, zinc, hot-dip galvanized) PARTSTABLE TECHNICAL DRAWING — NOT TO SCALE
KEY FEATURES
•
WASHER OUTSIDE DIAMETER: 0.649 INCHES MAXIMUM IN
•
WIDTH ACROSS FLATS: 0.430 INCHES MINIMUM AND 0.439 INCHES MAXIMUM IN
•
SURFACE TREATMENT DOCUMENT AND CLASSIFICATION: QQ-P-416,TYPE 2,CLASS 2 FED SPEC SINGLE TREATMENT RESPONSE OVERALL
•
THREAD SERIES: UNIFIED NATIONAL JOINT FINE (UNJF)
•
TEMP RATING: 450.0 FAHRENHEIT MAXIMUM DEGF
•
HARDNESS RATING: 44.0 ROCKWELL C MAXIMUM
•
WASHER THICKNESS: 0.065 INCHES MAXIMUM IN
TECHNICAL CHARACTERISTICS
OVERALL HEIGHT0.350 INCHES MAXIMUM IN
WASHER OUTSIDE DIAMETER0.649 INCHES MAXIMUM IN
WIDTH ACROSS FLATS0.430 INCHES MINIMUM AND 0.439 INCHES MAXIMUM IN
SURFACE TREATMENT DOCUMENT AND CLASSIFICATIONQQ-P-416,TYPE 2,CLASS 2 FED SPEC SINGLE TREATMENT RESPONSE OVERALL
THREAD SERIESUNIFIED NATIONAL JOINT FINE (UNJF)
TEMP RATING450.0 FAHRENHEIT MAXIMUM DEGF
HARDNESS RATING44.0 ROCKWELL C MAXIMUM
WASHER THICKNESS0.065 INCHES MAXIMUM IN
MATERIAL DOCUMENT AND CLASSIFICATIONAMS 6485 ASSN STD 2ND MATERIAL RESPONSE OR AMS 6487 ASSN STD 2ND MATERIAL RESPONSE OVERALL
THREAD DIRECTIONRIGHT-HAND
OTHER ITEMS IN FSC 5310 — Nuts and Washers
Items in the same Federal Supply class. No interchangeability or substitution relationship is implied.
5310-00-000-0040 5310-00-000-0077 5310-00-000-0079 5310-00-000-1146 5310-00-000-3815 5310-00-000-4532 5310-00-000-4540
SUBSTITUTES & CROSS-REFERENCES 1
GN511AA624MReference document
Same NSN cross-reference
Reference document — Vendor item drawing reference
LIFECYCLE
NSN statusActive· U.S. Government catalog
Acquisition advice: Terminal item — no further procurement; issued until stock is exhaustedNo demilitarization required
Ready to buy 74638M624?
Compare prices from verified sellers on eBay
Buy on eBay →
As an eBay Partner, PartsTable may earn a commission. Your price is not affected.
FREQUENTLY ASKED QUESTIONS
What is 74638M624?
74638M624 is a NUT,PLAIN,EXTENDED WASHER,DOUBLE.
What parts can replace 74638M624?
There is 1 known substitute for 74638M624: GN511AA624M. Substitute compatibility should be verified for your specific system.
What is the NSN for 74638M624?
74638M624 is cataloged in the U.S. Government catalog under NSN 5310-01-059-0259. This indicates validated use in U.S. government and defense supply chains.
Community Feedback
Leave a Comment
Comments are reviewed before appearing. You will receive an email to verify before your comment appears.

Request a Quote — 74638M624

✓ PartsTable — the parts reference. Every fact cited to its source.
PartsTable Design LLC · partstable.com
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.
PartsTable commercial catalog: edition Unified commercial catalog snapshot through 2026-09-28, edition date not on file, retrieved 2026-09-28.