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BACS21X11R — STUD ASSEMBLY,TURNLOCK FASTENER

✓ Government record, cited
— · BOLT SCREW
PRODUCT OVERVIEW

BACS21X11R: STUD ASSEMBLY,TURNLOCK FASTENER.

STUD ASSEMBLY,TURNLOCK FASTENER. Key specifications include diameter: 0.377 INCHES MINIMUM AND 0.384 INCHES MAXIMUM IN, material: STEEL COMP 4037 STUD, drive_type: CROSS RECESS, eyelet_length: 0.472 INCHES NOMINAL IN, stud_head_height: 0.102 INCHES NOMINAL IN, surface_treatment: CADMIUM AND CHROMATE OVERALL. This part is cataloged in the U.S.

Government catalog under NSN 5325-00-757-2930, 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
BACS21X11R
NSN: 5325-00-757-2930
FSC: 5325 — Fastening Devices
CAGE: 81205 — THE BOEING COMPANY DIV DEFENSE (USA)
SPECIFICATIONS
diameter0.377 INCHES MINIMUM AND 0.384 INCHES MAXIMUM IN
materialSTEEL COMP 4037 STUD
drive_typeCROSS RECESS
eyelet_length0.472 INCHES NOMINAL IN
stud_head_height0.102 INCHES NOMINAL IN
surface_treatmentCADMIUM AND CHROMATE OVERALL
stud_assembly_styleSTUD ASSEMBLY
eyelet_outside_diameter0.341 INCHES MINIMUM AND 0.348 INCHES MAXIMUM IN
turnlock_stud_head_styleSTUD HEAD
material_accommodated_thickness0.351 INCHES MINIMUM AND 0.380 INCHES MAXIMUM IN
material_document_and_classificationQQ-W-470 FED SPEC SINGLE MATERIAL RESPONSE PIN
surface_treatment_document_and_classificationQQ-P-416,TY 2,CL 2 FED SPEC SINGLE TREATMENT RESPONSE OVERALL
NSN5325-00-757-2930
COMPONENT DIAGRAM
BOLT / SCREW — THREAD VERIFICATION REQUIRED Hex HEAD LENGTH: — THREAD: — × — MATERIAL: — PN: BACS21X11R · OEM ⚠ VERIFY BEFORE ORDERING Verify thread pitch before ordering — metric (M8×1.25) ≠ imperial (5/16-18). Wrong thread = wrong part. Grade/class stamped on bolt head determines tensile strength ✓ BROKER TIP Grade/class stamped on head determines tensile strength. Grade 8 > Grade 5 > Grade 2. Always confirm head marking matches specification requirement PARTSTABLE TECHNICAL DRAWING — NOT TO SCALE
KEY FEATURES
•
SURFACE TREATMENT DOCUMENT AND CLASSIFICATION: QQ-P-416,TY 2,CL 2 FED SPEC SINGLE TREATMENT RESPONSE OVERALL
•
EYELET OUTSIDE DIAMETER: 0.341 INCHES MINIMUM AND 0.348 INCHES MAXIMUM IN
•
DRIVE TYPE: CROSS RECESS
•
MATERIAL ACCOMMODATED THICKNESS: 0.351 INCHES MINIMUM AND 0.380 INCHES MAXIMUM IN
•
MATERIAL DOCUMENT AND CLASSIFICATION: QQ-W-470 FED SPEC SINGLE MATERIAL RESPONSE PIN
•
DIAMETER: 0.377 INCHES MINIMUM AND 0.384 INCHES MAXIMUM IN
•
STUD HEAD HEIGHT: 0.102 INCHES NOMINAL IN
TECHNICAL CHARACTERISTICS
SURFACE TREATMENT DOCUMENT AND CLASSIFICATIONQQ-P-416,TY 2,CL 2 FED SPEC SINGLE TREATMENT RESPONSE OVERALL
EYELET OUTSIDE DIAMETER0.341 INCHES MINIMUM AND 0.348 INCHES MAXIMUM IN
DRIVE TYPECROSS RECESS
MATERIAL ACCOMMODATED THICKNESS0.351 INCHES MINIMUM AND 0.380 INCHES MAXIMUM IN
MATERIAL DOCUMENT AND CLASSIFICATIONQQ-W-470 FED SPEC SINGLE MATERIAL RESPONSE PIN
MATERIAL DOCUMENT AND CLASSIFICATIONQQ-W-470 FED SPEC SINGLE MATERIAL RESPONSE EJECTOR SPRING
DIAMETER0.377 INCHES MINIMUM AND 0.384 INCHES MAXIMUM IN
STUD HEAD HEIGHT0.102 INCHES NOMINAL IN
DISTANCE FROM ENGAGING MEMBER TO LARGEST BEARING SURFACE OF HEAD0.643 INCHES MINIMUM AND 0.653 INCHES MAXIMUM IN
TURNLOCK STUD HEAD STYLESTUD HEAD
SUBSTITUTES & CROSS-REFERENCES 7
40S5-11Same NSN cross-reference
Same NSN cross-reference
Also cataloged under this NSN
BACS21ED11RReference document
Same NSN cross-reference
Reference document — Vendor item drawing reference
12861-899-43Reference document
Same NSN cross-reference
Reference document — Advisory reference — outside the item-of-supply concept
5325PL0952596Reference document
Same NSN cross-reference
Reference document — Informative reference only
4002-11Same NSN cross-reference
Same NSN cross-reference
Also cataloged under this NSN
40S119-11-4BBSame NSN cross-reference
Same NSN cross-reference
Also cataloged under this NSN
LIFECYCLE
NSN statusActive· U.S. Government catalog
No demilitarization required
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FREQUENTLY ASKED QUESTIONS
What is BACS21X11R?
BACS21X11R is a STUD ASSEMBLY,TURNLOCK FASTENER.
What parts can replace BACS21X11R?
There are 7 known substitutes for BACS21X11R: 40S5-11, BACS21ED11R, 12861-899-43 and 4 more. Substitute compatibility should be verified for your specific system.
What is the NSN for BACS21X11R?
BACS21X11R is cataloged in the U.S. Government catalog under NSN 5325-00-757-2930. This indicates validated use in U.S. government and defense supply chains.
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✓ 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.