First End Distance From Keyway Center to End: 0.634 INCHES NOMINAL IN
First End Style: INDENTED FLAT KEYWAY AND CROSS DRILLED HOLE
Material Document and Classification: QQ-S-763,COND B FED SPEC SINGLE MATERIAL RESPONSE
First End Keyway Depth: 0.106 INCHES MINIMUM AND 0.121 INCHES MAXIMUM IN
End Similarity: IDENTICAL
First End Hole Diameter: 0.2180 INCHES NOMINAL IN
Identification
NSN: 3040-01-126-7378
NIIN: 011267378
FSC: 3040 — Miscellaneous Power Transmission Equipment
FSG: 30 — Mechanical Power Transmission Equipment
General Description
The Shaft,straight, cataloged under National Stock Number 3040-01-126-7378, is classified within Federal Supply Class 3040 (Miscellaneous Power Transmission Equipment) of the Mechanical Power Transmission Equipment group. Government technical data includes 10 specifications, cited from the U.S. Government catalog. 5 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 8 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
Technical Specifications
Parameter
Value
NSN
3040-01-126-7378
Item Name
Shaft,straight
FSC / FSG
3040 / 30 — Miscellaneous Power Transmission Equipment
Status
ACTIVE
First End Diameter
0.7500 INCHES NOMINAL IN
First End Distance From Keyway Center to End
0.634 INCHES NOMINAL IN
First End Style
INDENTED FLAT KEYWAY AND CROSS DRILLED HOLE
Material Document and Classification
QQ-S-763,COND B FED SPEC SINGLE MATERIAL RESPONSE
First End Keyway Depth
0.106 INCHES MINIMUM AND 0.121 INCHES MAXIMUM IN
End Similarity
IDENTICAL
First End Hole Diameter
0.2180 INCHES NOMINAL IN
Material
STEEL COMP 304
External Keyway Length
0.940 INCHES NOMINAL FIRST END IN
First End Keyway Width
0.1880 INCHES MINIMUM AND 0.1900 INCHES MAXIMUM IN
Lifecycle & Compliance
Acquisition Status
ACTIVE
DEMIL Code
DEMIL A — No Demilitarization Required
Hazard
No hazard code in the DLA record (HMIC N)
Criticality Code
X
⇄Related Items8
Each row states its source: a government interchangeability/replacement code, or a possible match on a shared part number.
3040-01-151-563487832-1641 ITEM 35POSSIBLE MATCH
SHAFT,STRAIGHT
Possible match (shared part number)Electric Boat Corporation Div General Dynamics Electric Boat
3040-01-151-563587832-1641 ITEM 36POSSIBLE MATCH
SHAFT,STRAIGHT
Possible match (shared part number)Electric Boat Corporation Div General Dynamics Electric Boat
3020-01-151-806987832-1641 ITEM 14POSSIBLE MATCH
GEAR,SPUR
Possible match (shared part number)Electric Boat Corporation Div General Dynamics Electric Boat
3020-01-152-023087832-1641 ITEM 29POSSIBLE MATCH
GEAR,SPUR
Possible match (shared part number)Electric Boat Corporation Div General Dynamics Electric Boat
3040-01-152-064587832-1641 ITEM 23POSSIBLE MATCH
SHAFT,SHOULDERED
Possible match (shared part number)Electric Boat Corporation Div General Dynamics Electric Boat
3020-01-152-087887832-1641 ITEM 15POSSIBLE MATCH
GEAR,SPUR
Possible match (shared part number)Electric Boat Corporation Div General Dynamics Electric Boat
3040-01-152-921787832-1641 ITEM 30POSSIBLE MATCH
SHAFT,SHOULDERED
Possible match (shared part number)Electric Boat Corporation Div General Dynamics Electric Boat
3020-01-163-2693709-4684912 ITEM 13POSSIBLE MATCH
GEAR,SPUR
Possible match (shared part number)Naval Sea Systems Command
Cross-Reference Index
No manufacturer part numbers on file in the U.S. Government catalog.
Reference documents
Reference
Meaning
709-4684912 ITEM 34
5/2Secondary reference
U.S. Government activity
87832-1641 ITEM 34
3/2Design control — primary reference
U.S. Government activity
87832-1641
D/9Drawing number reference only
U.S. Government activity
709-4684912 ITE
C/1Advisory reference — outside the item-of-supply concept
Naval Sea Systems Command
709-4684912
D/9Drawing number reference only
U.S. Government activity
Related Parts
3040-01-151-5634POSSIBLE MATCH
SHAFT,STRAIGHT
87832-1641 ITEM 35
3040-01-151-5635POSSIBLE MATCH
SHAFT,STRAIGHT
87832-1641 ITEM 36
3020-01-151-8069POSSIBLE MATCH
GEAR,SPUR
87832-1641 ITEM 14
3020-01-152-0230POSSIBLE MATCH
GEAR,SPUR
87832-1641 ITEM 29
3040-01-152-0645POSSIBLE MATCH
SHAFT,SHOULDERED
87832-1641 ITEM 23
3020-01-152-0878POSSIBLE MATCH
GEAR,SPUR
87832-1641 ITEM 15
3040-01-152-9217POSSIBLE MATCH
SHAFT,SHOULDERED
87832-1641 ITEM 30
3020-01-163-2693POSSIBLE MATCH
GEAR,SPUR
709-4684912 ITEM 13
Frequently Asked Questions
What is NSN 3040-01-126-7378?
NSN 3040-01-126-7378 is a Shaft,straight, classified under FSC 3040, Miscellaneous Power Transmission Equipment. Status: active.
What NSN replaces 3040-01-126-7378?
8 possible matches (shared part number, not a government interchangeability claim): 3040-01-151-5634, 3040-01-151-5635, 3020-01-151-8069. Verify interchangeability with system specifications before substitution.
What are the specifications of 3040-01-126-7378?
Key specifications for 3040-01-126-7378: First End Diameter: 0.7500 INCHES NOMINAL IN; First End Distance From Keyway Center to End: 0.634 INCHES NOMINAL IN; First End Style: INDENTED FLAT KEYWAY AND CROSS DRILLED HOLE; Material Document and Classification: QQ-S-763,COND B FED SPEC SINGLE MATERIAL RESPONSE. 10 specifications are documented in the U.S. Government catalog.
Is NSN 3040-01-126-7378 hazardous material?
No hazard code in the DLA record (HMIC N). Hazard information on this page is shown exactly as it appears in the DLA record.
Sources
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-16.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.
✓ Data cited from the U.S. Government catalog; commercial cross-references from OEM and certified industry sources.