The Muffler,exhaust, cataloged under National Stock Number 2990-01-025-4253, is classified within Federal Supply Class 2990 (Miscellaneous Engine Accessories, Nonaircraft) of the Engine Accessories group. Government technical data includes 14 specifications, cited from the U.S. Government catalog. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 2990-01-025-4253 |
| Item Name | Muffler,exhaust |
| FSC / FSG | 2990 / 29 — Miscellaneous Engine Accessories, Nonaircraft |
| Status | ACTIVE |
| Inlet Flange Shape | ROUND SINGLE INLET |
| Operating Position | UNIVERSAL |
| Inlet Location | CENTRALLY LOCATED IN END SECTION OF BODY |
| Design Type | JACKETED |
| Overall Diameter | 5.250 INCHES NOMINAL IN |
| Inlet Projection Length | 1.938 INCHES NOMINAL SINGLE INLET IN |
| Material Document and Classification | FRG-W820210-A MFR REF SINGLE MATERIAL RESPONSE LOCATION NOT OTHERWISE SPECIFIED |
| Inlet Flange Mounting Hole Diameter | 0.562 INCHES NOMINAL SINGLE INLET IN |
| Muffler Design | LOUVER |
| Inlet Connection Type | FLANGE SINGLE INLET |
| Body Shape | ROUND |
| Inlet Flange Mounting Provision and Quantity | 6 HOLES SINGLE INLET |
| Material | NICKEL ALLOY LOCATION NOT OTHERWISE SPECIFIED |
| Material | COPPER ALLOY INSULATION |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Reference | Meaning |
|---|---|
| 140-86570-15S | 5/9 Secondary reference U.S. Government activity |
| 140-86570-15S 1 1-2IPS MONEL | 5/9 Secondary reference U.S. Government activity |
| 0311815 140-86570-15S | 5/9 Secondary reference U.S. Government activity |
| 0311815 | 3/2 Design control — primary reference U.S. Government activity |
NSN 2990-01-025-4253 is a Muffler,exhaust, classified under FSC 2990, Miscellaneous Engine Accessories, Nonaircraft. Status: active.
Key specifications for 2990-01-025-4253: Inlet Flange Shape: ROUND SINGLE INLET; Operating Position: UNIVERSAL; Inlet Location: CENTRALLY LOCATED IN END SECTION OF BODY; Design Type: JACKETED. 14 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.