The Gear Sector,spur, cataloged under National Stock Number 3020-01-115-2137, is classified within Federal Supply Class 3020 (Gears, Pulleys, Sprockets, and Transmission Chain) of the Mechanical Power Transmission Equipment group. The manufacturer of record is Huntington Ingalls Inc Div Newport News Shipbuilding. Government technical data includes 15 specifications, cited from the U.S. Government catalog. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 3020-01-115-2137 |
| Primary Part Number | 2730-79 ITEM 21 |
| Item Name | Gear Sector,spur |
| FSC / FSG | 3020 / 30 — Gears, Pulleys, Sprockets, and Transmission Chain |
| Manufacturer | Huntington Ingalls Inc Div Newport News Shipbuilding |
| Status | ACTIVE |
| Bore Nominal Diameter | 0.855 INCHES BOTH ENDS IN |
| Hub Nominal Diameter | 1.1250 INCHES FIRST END IN |
| Teeth Quantity | 34 |
| Nominal Outside Radius | 2.2500 INCHES IN |
| Bore Style | STRAIGHT SPLINE BOTH ENDS |
| Nominal Distance Between Body Face and Protruding Hub End | 0.2500 INCHES FIRST END IN |
| Style Designator | PROTRUDING HUB |
| Material Document and Classification | QQ-N-281,CLASS A FED SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Tooth Form | STANDARD |
| Hub Style Designator | PINNED FIRST END |
| Spline Quantity | 10 BOTH ENDS |
| Pitch Radius | 2.1250 INCHES NOMINAL IN |
| Pressure Angle | 20.0000 DEGREES |
| Material | NICKEL ALLOY 400 OVERALL |
| Face Nominal Width | 0.375 INCHES IN |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| 2730-79 ITEM 21 | Huntington Ingalls Inc Div Newport News Shipbuilding (USA) |
| Reference | Meaning |
|---|---|
| 2730-79 | D/9 Drawing number reference only Huntington Ingalls Inc Div Newport News Shipbuilding |
| 501-4456540 ITEM 21 | 3/2 Design control — primary reference U.S. Government activity |
| 501-4456540 | D/9 Drawing number reference only U.S. Government activity |
| 01-4456540 ITEM | C/1 Advisory reference — outside the item-of-supply concept U.S. Government activity |
NSN 3020-01-115-2137 is a Gear Sector,spur, manufactured by Huntington Ingalls Inc Div Newport News Shipbuilding, classified under FSC 3020, Gears, Pulleys, Sprockets, and Transmission Chain. Status: active.
NSN 3020-01-115-2137 has 1 manufacturer part number on file: 2730-79 ITEM 21 (Huntington Ingalls Inc Div Newport News Shipbuilding).
2 possible matches (shared part number, not a government interchangeability claim): 4820-01-188-3703, 4820-01-216-4162. Verify interchangeability with system specifications before substitution.
Key specifications for 2730-79 ITEM 21: Bore Nominal Diameter: 0.855 INCHES BOTH ENDS IN; Hub Nominal Diameter: 1.1250 INCHES FIRST END IN; Teeth Quantity: 34; Nominal Outside Radius: 2.2500 INCHES IN. 15 specifications are documented in the U.S. Government catalog.
No hazard code in the DLA record (HMIC N). Hazard information on this page is shown exactly as it appears in the DLA record.
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.