The Seat,valve, cataloged under National Stock Number 4820-00-593-4903, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Tyco Fire Products Lp. Government technical data includes 7 specifications, cited from the U.S. Government catalog. The record lists 3 manufacturer part numbers 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 4820-00-593-4903 |
| Primary Part Number | 20-03542ITEM1 |
| Item Name | Seat,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Tyco Fire Products Lp |
| Status | ACTIVE |
| Body Outside Diameter | 1.750 INCHES NOMINAL IN |
| Seal Accommodation Type | BEADED |
| Style Designator | PLAIN |
| Body Inside Diameter | 0.938 INCHES NOMINAL IN |
| Material | PLASTIC POLYAMIDE NYLON OVERALL |
| Seat Angle in Deg | 37.000 NOMINAL |
| Seating Surface Shape | ANGULAR |
| 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 |
|---|---|
| 20-03542ITEM1 PRIMARY | Tyco Fire Products Lp (USA) |
| V-3181 PRIMARY | Portland Valve Llc (USA) |
| 20-03181 PRIMARY | Tyco Fire Products Lp (USA) |
| Reference | Meaning |
|---|---|
| V3542ITEM1 | 5/9 Secondary reference Tyco Fire Products Lp |
| V3181 | 5/9 Secondary reference Tyco Fire Products Lp |
NSN 4820-00-593-4903 is a Seat,valve, manufactured by Tyco Fire Products Lp, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-00-593-4903 has 3 manufacturer part numbers on file: 20-03542ITEM1 (Tyco Fire Products Lp), V-3181 (Portland Valve Llc), 20-03181 (Tyco Fire Products Lp).
1 possible match (shared part number, not a government interchangeability claim): 6150-01-208-3424. Verify interchangeability with system specifications before substitution.
Key specifications for 20-03542ITEM1: Overall Height: 0.344 INCHES NOMINAL IN; Body Outside Diameter: 1.750 INCHES NOMINAL IN; Seal Accommodation Type: BEADED; Style Designator: PLAIN. 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.