The Stem,support,valve, cataloged under National Stock Number 4820-01-434-5312, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Automatic Switch Company Dba Asco. Government technical data includes 1 specification, 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. 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 | 4820-01-434-5312 |
| Primary Part Number | 031990 |
| Item Name | Stem,support,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Automatic Switch Company Dba Asco |
| Status | ACTIVE |
| Material | COPPER ALLOY |
| 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 |
|---|---|
| 031990 PRIMARY | Automatic Switch Company Dba Asco (USA) |
| AV 262533 ITEM 1K | Automatic Switch Company Dba Asco (USA) |
| AV 262534 ITEM 1N | Automatic Switch Company Dba Asco (USA) |
NSN 4820-01-434-5312 is a Stem,support,valve, manufactured by Automatic Switch Company Dba Asco, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-434-5312 has 3 manufacturer part numbers on file: 031990 (Automatic Switch Company Dba Asco), AV 262533 ITEM 1K (Automatic Switch Company Dba Asco), AV 262534 ITEM 1N (Automatic Switch Company Dba Asco).
1 possible match (shared part number, not a government interchangeability claim): 6515-01-515-5396. Verify interchangeability with system specifications before substitution.
Key specifications for 031990: Special Features: SWITCH OPERATING TYPE; End Item Identification: SEAWOLF CLASS SSN; Material: COPPER ALLOY. 1 specification is 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.