The Magneto,ignition, cataloged under National Stock Number 2920-00-242-9505, is classified within Federal Supply Class 2920 (Engine Electrical System Components, Nonaircraft) of the Engine Accessories group. The manufacturer of record is Dresser Industries Inc Leroi Div. Government technical data includes 18 specifications, cited from the U.S. Government catalog. The record lists 3 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 7 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government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 | 2920-00-242-9505 |
| Primary Part Number | A85-187 |
| Item Name | Magneto,ignition |
| FSC / FSG | 2920 / 29 — Engine Electrical System Components, Nonaircraft |
| Manufacturer | Dresser Industries Inc Leroi Div |
| Status | ACTIVE |
| Mounting Standard Controlling Agency | SAE |
| Mounting Facility Quantity | 2 |
| Mounting Slot Length | 1.137 INCHES NOMINAL IN |
| Mounting Method | FLANGE |
| Drive Connection Type | IMPULSE COUPLED |
| Pole Quantity | 2 |
| Mounting Facility Thread Quantity Per Inch | 16 |
| Shaft Rotation Direction | COUNTERCLOCKWISE |
| Distance Between Mounting Facility Centers | 4.182 INCHES MINIMUM AND 4.194 INCHES MAXIMUM IN |
| Body Material | ALUMINUM ALLOY |
| Mounting Facility Thread Diameter | 0.375 INCHES NOMINAL IN |
| Impulse Quantity Per Revolution | 4 |
| Contact Set Quantity | 1 |
| Mounting Facility | SLOT AND THREADED HOLE(S) |
| Ignition Type for Which Designed | SINGLE |
| Performance Type | HIGH TENSION |
| Rotation Element Type | PERMANENT MAGNET ROTOR |
| Mounting Slot Width | 0.403 INCHES MINIMUM AND 0.414 INCHES MAXIMUM 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 |
|---|---|
| A85-187 | Dresser Industries Inc Leroi Div (USA) |
| MRD4A301 | United Technologies Corp Electro Systems Inc (USA) |
| A85-179-14 | Dresser Industries Inc Leroi Div (USA) |
| Reference | Meaning |
|---|---|
| H24-526 | 3/9 Design control — primary reference U.S. Government activity |
| MJH4C301 | 5/9 Secondary reference Ambac International Corporation Div Ambac International |
| H24-526 | 5/9 Secondary reference U.S. Government activity |
| MRD4A301 | 5/9 Secondary reference Ambac International Corporation Div Ambac International |
| 24526 | 5/9 Secondary reference Lucas Aerospace Power Equipment Corporation |
| 24526 | 5/9 Secondary reference U.S. Government activity |
| H24-526 | 5/9 Secondary reference Lucas Aerospace Power Equipment Corporation |
NSN 2920-00-242-9505 is a Magneto,ignition, manufactured by Dresser Industries Inc Leroi Div, classified under FSC 2920, Engine Electrical System Components, Nonaircraft. Status: active.
NSN 2920-00-242-9505 has 3 manufacturer part numbers on file: A85-187 (Dresser Industries Inc Leroi Div), MRD4A301 (United Technologies Corp Electro Systems Inc), A85-179-14 (Dresser Industries Inc Leroi Div).
2 possible matches (shared part number, not a government interchangeability claim): 3120-01-168-9953, 5998-01-343-5565. Verify interchangeability with system specifications before substitution.
Key specifications for A85-187: Mounting Standard Controlling Agency: SAE; Mounting Facility Quantity: 2; Mounting Slot Length: 1.137 INCHES NOMINAL IN; Mounting Method: FLANGE. 18 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.