The Pneumatic Muffler,exhaust-Intake, cataloged under National Stock Number 4310-01-491-3922, is classified within Federal Supply Class 4310 (Compressors and Vacuum Pumps) of the Pumps and Compressors group. Government technical data includes 3 specifications, cited from the U.S. Government catalog. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government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 | 4310-01-491-3922 |
| Item Name | Pneumatic Muffler,exhaust-Intake |
| FSC / FSG | 4310 / 43 — Compressors and Vacuum Pumps |
| Status | ACTIVE |
| Overall Diameter | 12.750 INCHES NOMINAL IN |
| Body Shape | ROUND |
| Material | COPPER ALLOY 706 LOCATION NOT OTHERWISE SPECIFIED |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL D — Destroy Item |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Reference | Meaning |
|---|---|
| 2621-126-01 ASSY 99 | 3/9 Design control — primary reference U.S. Government activity |
| 2621-126-01 | D/9 Drawing number reference only U.S. Government activity |
| 262112601-0099 | 3/2 Design control — primary reference U.S. Government activity |
NSN 4310-01-491-3922 is a Pneumatic Muffler,exhaust-Intake, classified under FSC 4310, Compressors and Vacuum Pumps. Status: active.
2 possible matches (shared part number, not a government interchangeability claim): 4320-01-495-2616, 6685-01-686-8098. Verify interchangeability with system specifications before substitution.
Key specifications for 4310-01-491-3922: Overall Diameter: 12.750 INCHES NOMINAL IN; Overall Length: 35.230 INCHES NOMINAL IN; Body Shape: ROUND; Special Features: 12.00 NPS PIPE; 6.75 IN. HOLE THROUGH ONE SIDE AT LENGTH 19.570 IN. IN. 3 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.
NSN 4310-01-491-3922 has DEMIL Code D. Demilitarization may be required before disposal or transfer to non-military entities.
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.