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BACS21AE6A4 — STUD ASSEMBLY,TURNLOCK FASTENER

✓ Government record, cited
— · BOLT SCREW
PRODUCT OVERVIEW

BACS21AE6A4: STUD ASSEMBLY,TURNLOCK FASTENER.

STUD ASSEMBLY,TURNLOCK FASTENER. Key specifications include diameter: 0.380 INCHES NOMINAL IN, material: STEEL OVERALL, drive_type: CROSS RECESS, eyelet_length: 0.380 INCHES NOMINAL IN, surface_treatment: CADMIUM OVERALL, stud_assembly_style: STUD ASSEMBLY. This part is cataloged in the U.S.

Government catalog under NSN 5325-00-708-4987, 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
BACS21AE6A4
NSN: 5325-00-708-4987
FSC: 5325 — Fastening Devices
CAGE: 81205 — THE BOEING COMPANY DIV DEFENSE (USA)
SPECIFICATIONS
diameter0.380 INCHES NOMINAL IN
materialSTEEL OVERALL
drive_typeCROSS RECESS
eyelet_length0.380 INCHES NOMINAL IN
surface_treatmentCADMIUM OVERALL
stud_assembly_styleSTUD ASSEMBLY
securing_device_typeRING
eyelet_outside_diameter0.373 INCHES NOMINAL IN
turnlock_stud_head_styleFLAT COUNTERSUNK
material_accommodated_thickness0.258 INCHES MINIMUM AND 0.357 INCHES MAXIMUM IN
distance_from_engaging_member_to_largest_bearing_surface_of_head0.646 INCHES NOMINAL IN
NSN5325-00-708-4987
COMPONENT DIAGRAM
BOLT / SCREW — THREAD VERIFICATION REQUIRED Hex HEAD LENGTH: — THREAD: — × — MATERIAL: — PN: BACS21AE6A4 · 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
•
EYELET OUTSIDE DIAMETER: 0.373 INCHES NOMINAL IN
•
DRIVE TYPE: CROSS RECESS
•
MATERIAL ACCOMMODATED THICKNESS: 0.258 INCHES MINIMUM AND 0.357 INCHES MAXIMUM IN
•
DIAMETER: 0.380 INCHES NOMINAL IN
•
SECURING DEVICE TYPE: RING
•
DISTANCE FROM ENGAGING MEMBER TO LARGEST BEARING SURFACE OF HEAD: 0.646 INCHES NOMINAL IN
•
TURNLOCK STUD HEAD STYLE: FLAT COUNTERSUNK
•
SURFACE TREATMENT: CADMIUM OVERALL
TECHNICAL CHARACTERISTICS
EYELET OUTSIDE DIAMETER0.373 INCHES NOMINAL IN
DRIVE TYPECROSS RECESS
MATERIAL ACCOMMODATED THICKNESS0.258 INCHES MINIMUM AND 0.357 INCHES MAXIMUM IN
DIAMETER0.380 INCHES NOMINAL IN
SECURING DEVICE TYPERING
DISTANCE FROM ENGAGING MEMBER TO LARGEST BEARING SURFACE OF HEAD0.646 INCHES NOMINAL IN
TURNLOCK STUD HEAD STYLEFLAT COUNTERSUNK
SURFACE TREATMENTCADMIUM OVERALL
MATERIALSTEEL OVERALL
STUD ASSEMBLY STYLESTUD ASSEMBLY
OTHER ITEMS IN FSC 5325 — Fastening Devices
Items in the same Federal Supply class. No interchangeability or substitution relationship is implied.
5325-00-000-1884 5325-00-000-9988 5325-00-001-1567 5325-00-001-2043 5325-00-001-3842 5325-00-001-3858 5325-00-001-3871 5325-00-001-4317
SUBSTITUTES & CROSS-REFERENCES 1
4S14-6-4Same 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 BACS21AE6A4?
BACS21AE6A4 is a STUD ASSEMBLY,TURNLOCK FASTENER.
What parts can replace BACS21AE6A4?
There is 1 known substitute for BACS21AE6A4: 4S14-6-4. Substitute compatibility should be verified for your specific system.
What is the NSN for BACS21AE6A4?
BACS21AE6A4 is cataloged in the U.S. Government catalog under NSN 5325-00-708-4987. 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.