The Muffler,exhaust, cataloged under National Stock Number 2990-01-112-5737, is classified within Federal Supply Class 2990 (Miscellaneous Engine Accessories, Nonaircraft) of the Engine Accessories group. The manufacturer of record is Macleod Inc. Government technical data includes 16 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 2990-01-112-5737 |
| Primary Part Number | B1900-5118 |
| Item Name | Muffler,exhaust |
| FSC / FSG | 2990 / 29 — Miscellaneous Engine Accessories, Nonaircraft |
| Manufacturer | Macleod Inc |
| Status | ACTIVE |
| Operating Position | UNIVERSAL |
| Inlet Location | CENTRALLY LOCATED IN END SECTION OF BODY |
| Coolant Type | WATER |
| Design Type | DRY |
| Overall Diameter | 3.000 INCHES NOMINAL IN |
| Outlet Inside Diameter | 1.625 INCHES NOMINAL FIRST OUTLET IN |
| Inlet Projection Length | 3.000 INCHES NOMINAL SINGLE INLET IN |
| Muffler Design | STRAIGHT THROUGH |
| Inlet Connection Type | UNTHREADED SINGLE INLET |
| Body Shape | ROUND |
| Inlet Inside Diameter | 1.625 INCHES NOMINAL SINGLE INLET IN |
| Inlet Integral Manifold Exhaust Pipe Length | 1.625 INCHES NOMINAL SINGLE INLET IN |
| Material | STEEL LOCATION NOT OTHERWISE SPECIFIED |
| Outlet Projection Length | 3.000 INCHES NOMINAL FIRST OUTLET IN |
| Outlet Connection Type | UNTHREADED FIRST OUTLET |
| Outlet Location | CENTRALLY LOCATED IN END SECTION OF BODY |
| 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 |
|---|---|
| B1900-5118 PRIMARY | Macleod Inc (USA) |
| Reference | Meaning |
|---|---|
| 21728 | 5/9 Secondary reference U.S. Government activity |
| E-W-B1900-5100 | D/9 Drawing number reference only Macleod Inc |
NSN 2990-01-112-5737 is a Muffler,exhaust, manufactured by Macleod Inc, classified under FSC 2990, Miscellaneous Engine Accessories, Nonaircraft. Status: active.
NSN 2990-01-112-5737 has 1 manufacturer part number on file: B1900-5118 (Macleod Inc).
Key specifications for B1900-5118: Operating Position: UNIVERSAL; Inlet Location: CENTRALLY LOCATED IN END SECTION OF BODY; Coolant Type: WATER; Design Type: DRY. 16 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.