The Muffler,special, cataloged under National Stock Number 2990-01-679-4209, is classified within Federal Supply Class 2990 (Miscellaneous Engine Accessories, Nonaircraft) of the Engine Accessories group. The manufacturer of record is Naval Sea Systems Command. Government technical data includes 4 specifications, cited from the U.S. Government catalog. The record lists 2 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 5 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 2990-01-679-4209 |
| Primary Part Number | 515-6985002-A7 |
| Item Name | Muffler,special |
| FSC / FSG | 2990 / 29 — Miscellaneous Engine Accessories, Nonaircraft |
| Manufacturer | Naval Sea Systems Command |
| Status | ACTIVE |
| General Characteristics Item Description | MUFFLER/DIFFUSER ASSEMBLY REQUIRES SHOCK QUALIFICATION I/A/W SECTION 072 OF THE NSSN CLASS SHIPS SPECIFICATIONS AND PPD 802-6337447, DDAM PROCEDURES; THE FOLLOWING ATTRIBUTES APPLY: SHOCK QUALIFICATION METHOD: ANALYSIS; SHOCK TEST CATEGORY: NOT AVAILABLE; SHOCK GRADE: B; EQUIPMENT TEST/ANALYSIS CLASS: NOT AVAILABLE; EQUIPMENT HOLD-DOWN MEANS: GRADE 500 SIZE 1.250; MATERIAL: QQ-N-286 CLASS A, SPECIFICATION: MIL-S-1222H; SHOCK TEST TYPE: NOT AVAILABLE; MOUNTING LOCATION (SHIPBOARD): WETTED SURFACE; MOUNTING PLANE (SHIPBOARD): NOT AVAILABLE; MOUNTING ORIENTATION (SHIPBOARD): NOT AVAILABLE; LIMITATIONS: NONE; QUALIFICATION APPROVAL DOCUMENT (IF COMPLETE) IS REFERENCED IN THE DOCUMENT FIELD WITHIN THE PART DESCRIPTION(S) |
| Special Test Features | REFER TO EB SPECIFICATION 4229; THE POLYMER FOR THE FOUR MUFFLER LAYERS SHALL BE RW-2577-82 I/A/W SECTION 3.4.1; THE FILLER MATERIAL FOR THE MUFFLER LAYERS SHALL BE I/A/W SECTION 2.1 OF APPENDIX A OF THE SPECIFICATION; THE % FILL FOR EACH LAYER SHALL BE I/A/W TABLE 1 OF APPENDIX A |
| Supplementary Features | NOISE CONTROL (SUBMARINE) |
| Specification/standard Data | 80204-ANSI Y14.5M-1982 PROFESSIONAL/INDUSTRIAL ASSOCIATION STANDARD |
| 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 |
|---|---|
| 515-6985002-A7 PRIMARY | Naval Sea Systems Command (USA) |
| H444-0601-A7 | Derbyshire Machine & Tool Co (USA) |
| Reference | Meaning |
|---|---|
| H444-0601-A7 | 5/1 Secondary reference U.S. Government activity |
| 6985002 | D/9 Drawing number reference only Naval Sea Systems Command |
| 515-6985002-31 | 5/9 Secondary reference Naval Sea Systems Command |
| H444-0601-31 | 5/9 Secondary reference U.S. Government activity |
| H444-0601-A7 | 5/2 Secondary reference U.S. Government activity |
NSN 2990-01-679-4209 is a Muffler,special, manufactured by Naval Sea Systems Command, classified under FSC 2990, Miscellaneous Engine Accessories, Nonaircraft. Status: active.
NSN 2990-01-679-4209 has 2 manufacturer part numbers on file: 515-6985002-A7 (Naval Sea Systems Command), H444-0601-A7 (Derbyshire Machine & Tool Co).
1 possible match (shared part number, not a government interchangeability claim): 5342-01-714-6060. Verify interchangeability with system specifications before substitution.
Key specifications for 515-6985002-A7: General Characteristics Item Description: MUFFLER/DIFFUSER ASSEMBLY REQUIRES SHOCK QUALIFICATION I/A/W SECTION 072 OF THE NSSN CLASS SHIPS SPECIFICATIONS AND PPD 802-6337447, DDAM PROCEDURES; THE FOLLOWING ATTRIBUTES APPLY: SHOCK QUALIFICATION METHOD: ANALYSIS; SHOCK TEST CATEGORY: NOT AVAILABLE; SHOCK GRADE: B; EQUIPMENT TEST/ANALYSIS CLASS: NOT AVAILABLE; EQUIPMENT HOLD-DOWN MEANS: GRADE 500 SIZE 1.250; MATERIAL: QQ-N-286 CLASS A, SPECIFICATION: MIL-S-1222H; SHOCK TEST TYPE: NOT AVAILABLE; MOUNTING LOCATION (SHIPBOARD): WETTED SURFACE; MOUNTING PLANE (SHIPBOARD): NOT AVAILABLE; MOUNTING ORIENTATION (SHIPBOARD): NOT AVAILABLE; LIMITATIONS: NONE; QUALIFICATION APPROVAL DOCUMENT (IF COMPLETE) IS REFERENCED IN THE DOCUMENT FIELD WITHIN THE PART DESCRIPTION(S); Special Test Features: REFER TO EB SPECIFICATION 4229; THE POLYMER FOR THE FOUR MUFFLER LAYERS SHALL BE RW-2577-82 I/A/W SECTION 3.4.1; THE FILLER MATERIAL FOR THE MUFFLER LAYERS SHALL BE I/A/W SECTION 2.1 OF APPENDIX A OF THE SPECIFICATION; THE % FILL FOR EACH LAYER SHALL BE I/A/W TABLE 1 OF APPENDIX A; Supplementary Features: NOISE CONTROL (SUBMARINE); Specification/standard Data: 80204-ANSI Y14.5M-1982 PROFESSIONAL/INDUSTRIAL ASSOCIATION STANDARD. 4 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.