Nominal Distance Between Body Face and Protruding Hub End: 0.250 INCHES FIRST END IN
Face Type: STRAIGHT
Identification
NSN: 3020-00-203-1678
NIIN: 002031678
FSC: 3020 — Gears, Pulleys, Sprockets, and Transmission Chain
FSG: 30 — Mechanical Power Transmission Equipment
General Description
The Gear,worm, cataloged under National Stock Number 3020-00-203-1678, is classified within Federal Supply Class 3020 (Gears, Pulleys, Sprockets, and Transmission Chain) of the Mechanical Power Transmission Equipment group. Government technical data includes 16 specifications, cited from the U.S. Government catalog. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 7 items share a part number with this NSN in the catalog (possible match — not a government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
3020-00-203-1678
Item Name
Gear,worm
FSC / FSG
3020 / 30 — Gears, Pulleys, Sprockets, and Transmission Chain
Status
ACTIVE
Thread Form Direction
LEFT-HAND
Bore Nominal Diameter
0.312 INCHES BOTH ENDS IN
Helix Angle
14.0333 DEGREES
Hub Nominal Diameter
0.425 INCHES FIRST END IN
Bore Style
PLAIN BOTH ENDS
Nominal Distance Between Body Face and Protruding Hub End
0.250 INCHES FIRST END IN
Face Type
STRAIGHT
Style Designator
PROTRUDING HUB
Pitch Diameter
0.5000 INCHES NOMINAL IN
Hub Style Designator
PLAIN FIRST END
Thread Form Quantity
4
Nominal Outside Diameter
0.562 INCHES IN
Surface Treatment
PHOSPHATE OVERALL
Pressure Angle
20.0000 DEGREES
Material
STEEL OVERALL
Face Nominal Width
1.000 INCHES 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 Items7
Each row states its source: a government interchangeability/replacement code, or a possible match on a shared part number.
4320-00-821-987950350-BZPOSSIBLE MATCH
PARTS KIT,ROTARY PUMP
Possible match (shared part number)Waterous Company
5340-00-853-482750350POSSIBLE MATCH
CLAMP,LOOP
Possible match (shared part number)Eaton Aeroquip Llc Dba Jackson North 1 Div Fluid and Electrical Distribution
5330-00-992-392950350POSSIBLE MATCH
PACKING ASSEMBLY
Possible match (shared part number)Sicard a Division of Smi-Snowblast Inc Dba Sicard
5950-01-112-235850350POSSIBLE MATCH
TRANSFORMER,POWER
Possible match (shared part number)Coiltron Inc Div Coiltron
5340-01-154-567750350POSSIBLE MATCH
BUTTON,PLUG
Possible match (shared part number)Kenworth Truck Co a Div of Paccar Inc
5210-01-366-43831U6679POSSIBLE MATCH
INDICATOR,DIAL
Possible match (shared part number)Caterpillar Inc Div Caterpillar Defense
5910-01-562-340150350POSSIBLE MATCH
CAPACITOR,FIXED,ELECTROLYTIC
Possible match (shared part number)Crispaire Corp Dba Marvair Co
Cross-Reference Index
No manufacturer part numbers on file in the U.S. Government catalog.
Reference documents
Reference
Meaning
SCB69681
5/2Secondary reference
U.S. Government activity
3020002031678
6/9Informative reference only
E.c.a Etablissement Central Des Approvisionnements Des Forces Armees Royales
50350
3/9Design control — primary reference
U.S. Government activity
Related Parts
4320-00-821-9879POSSIBLE MATCH
PARTS KIT,ROTARY PUMP
50350-BZ
5340-00-853-4827POSSIBLE MATCH
CLAMP,LOOP
50350
5330-00-992-3929POSSIBLE MATCH
PACKING ASSEMBLY
50350
5950-01-112-2358POSSIBLE MATCH
TRANSFORMER,POWER
50350
5340-01-154-5677POSSIBLE MATCH
BUTTON,PLUG
50350
5210-01-366-4383POSSIBLE MATCH
INDICATOR,DIAL
1U6679
5910-01-562-3401POSSIBLE MATCH
CAPACITOR,FIXED,ELECTROLYTIC
50350
Frequently Asked Questions
What is NSN 3020-00-203-1678?
NSN 3020-00-203-1678 is a Gear,worm, classified under FSC 3020, Gears, Pulleys, Sprockets, and Transmission Chain. Status: active.
What NSN replaces 3020-00-203-1678?
7 possible matches (shared part number, not a government interchangeability claim): 4320-00-821-9879, 5340-00-853-4827, 5330-00-992-3929. Verify interchangeability with system specifications before substitution.
What are the specifications of 3020-00-203-1678?
Key specifications for 3020-00-203-1678: Thread Form Direction: LEFT-HAND; Bore Nominal Diameter: 0.312 INCHES BOTH ENDS IN; Helix Angle: 14.0333 DEGREES; Hub Nominal Diameter: 0.425 INCHES FIRST END IN. 16 specifications are documented in the U.S. Government catalog.
Is NSN 3020-00-203-1678 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.