PartsTable
Technical Data Sheet
Download PDF

66278-12-SS-12 — NUT,PLAIN,CLINCH

✓ Government record, cited
— · NUT WASHER
PRODUCT OVERVIEW

66278-12-SS-12: NUT,PLAIN,CLINCH.

The NUT,PLAIN,CLINCH is a the manufacturer industrial component. Key specifications include material: STEEL COMP 303 OVERALL, nut_style: CLINCH, nut_height: 0.375 INCHES NOMINAL IN, thread_class: 2B, thread_series: UNIFIED NATIONAL COARSE (UNC), pilot_diameter: 0.212 INCHES MAXIMUM IN. This part is cataloged in the U.S.

Government catalog under NSN 5310-01-272-8329, 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
66278-12-SS-12
NSN: 5310-01-272-8329
FSC: 5310 — Nuts and Washers
CAGE: 51506 — ACCURATE SCREW MACHINE CORP DIV ACCURATE SCREW MACHINE CORPORATION (USA)
SPECIFICATIONS
materialSTEEL COMP 303 OVERALL
nut_styleCLINCH
nut_height0.375 INCHES NOMINAL IN
thread_class2B
thread_seriesUNIFIED NATIONAL COARSE (UNC)
pilot_diameter0.212 INCHES MAXIMUM IN
hardness_rating70.0 ROCKWELL B NOMINAL
thread_directionRIGHT-HAND
surface_treatmentPASSIVATE OVERALL
width_across_flats0.250 INCHES NOMINAL IN
nominal_thread_size0.112 INCHES IN
counterbore_diameter0.125 INCHES NOMINAL NUT IN
NSN5310-01-272-8329
COMPONENT DIAGRAM
NUT & WASHER — GRADE MATCHING REQUIRED Hex NUT CROSS-SECTION WASHER OD: — SIZE: — MATERIAL: — PN: 66278-12-SS-12 · 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
•
WIDTH ACROSS FLATS: 0.250 INCHES NOMINAL IN
•
THREAD SERIES: UNIFIED NATIONAL COARSE (UNC)
•
HARDNESS RATING: 70.0 ROCKWELL B NOMINAL
•
NUT COUNTERBORE DEPTH: 0.188 INCHES NOMINAL NUT IN
•
THREAD DIRECTION: RIGHT-HAND
•
NOMINAL THREAD SIZE: 0.112 INCHES IN
•
COUNTERBORE DIAMETER: 0.125 INCHES NOMINAL NUT IN
•
PILOT DIAMETER: 0.212 INCHES MAXIMUM IN
TECHNICAL CHARACTERISTICS
WIDTH ACROSS FLATS0.250 INCHES NOMINAL IN
THREAD SERIESUNIFIED NATIONAL COARSE (UNC)
HARDNESS RATING70.0 ROCKWELL B NOMINAL
NUT COUNTERBORE DEPTH0.188 INCHES NOMINAL NUT IN
THREAD DIRECTIONRIGHT-HAND
NOMINAL THREAD SIZE0.112 INCHES IN
COUNTERBORE DIAMETER0.125 INCHES NOMINAL NUT IN
PILOT DIAMETER0.212 INCHES MAXIMUM IN
NUT HEIGHT0.375 INCHES NOMINAL IN
SURFACE TREATMENTPASSIVATE OVERALL
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

No substitute or cross-reference records for this part.

LIFECYCLE
NSN statusActive· U.S. Government catalog
Acquisition advice: Normally procured from the manufacturer (OEM)No demilitarization required
Ready to buy 66278-12-SS-12?
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 66278-12-SS-12?
66278-12-SS-12 is a NUT,PLAIN,CLINCH.
What is the NSN for 66278-12-SS-12?
66278-12-SS-12 is cataloged in the U.S. Government catalog under NSN 5310-01-272-8329. 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 — 66278-12-SS-12

✓ 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.