The Damper,flue, cataloged under National Stock Number 4520-01-040-0899, is classified within Federal Supply Class 4520 (Space and Water Heating Equipment) of the Plumbing, Heating, and Waste Disposal group. Government technical data includes 7 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4520-01-040-0899 |
| Item Name | Damper,flue |
| FSC / FSG | 4520 / 45 — Space and Water Heating Equipment |
| Status | ACTIVE |
| Overall Diameter | 6.000 INCHES NOMINAL IN |
| Mounting Method | INSERTED CENTER SHAFT |
| Overall Thickness | 1.750 INCHES NOMINAL IN |
| Shape | ROUND |
| Surface Treatment | PAINT |
| Material | STEEL |
| Operation Method | MANUAL |
| 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 |
|---|---|
| NO4. SIZE 6 | 3/9 Design control — primary reference Hart & Cooley, Inc. |
| 4-6IN | 5/9 Secondary reference Tuttle and Bailey Div Allied Thermal Corp |
NSN 4520-01-040-0899 is a Damper,flue, classified under FSC 4520, Space and Water Heating Equipment. Status: active.
Key specifications for 4520-01-040-0899: Overall Height: 3.000 INCHES NOMINAL IN; Overall Diameter: 6.000 INCHES NOMINAL IN; Mounting Method: INSERTED CENTER SHAFT; Overall Thickness: 1.750 INCHES NOMINAL IN. 7 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.