The Retainer,disk,valve, cataloged under National Stock Number 4820-01-502-0510, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Trac Regulator Co., Inc. Dba Trac Regulator Co Inc. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government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.
| Item Name | Retainer,disk,valve |
| FSC / FSG | 4820 — Valves, Nonpowered (FSG 48) |
| Manufacturers | Trac Regulator Co., Inc. Dba Trac Regulator Co Inc (CAGE 55378) |
| Parameter | Value |
|---|---|
| NSN | 4820-01-502-0510 |
| Primary Part Number | P10857A |
| Item Name | Retainer,disk,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Trac Regulator Co., Inc. Dba Trac Regulator Co Inc |
| Status | ACTIVE |
| 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 |
|---|---|
| P10857A | Trac Regulator Co., Inc. Dba Trac Regulator Co Inc (USA) |
| Reference | Meaning |
|---|---|
| NAP-958 FIND NO.15 | 5/9 Secondary reference Atlas Valve Co |
| P10857A | 3/9 Design control — primary reference Atlas Valve Co |
| NAP 958 | D/9 Drawing number reference only Atlas Valve Co |
| NAP 958 CDS-1 | D/9 Drawing number reference only Atlas Valve Co |
NSN 4820-01-502-0510 is a Retainer,disk,valve, manufactured by Trac Regulator Co., Inc. Dba Trac Regulator Co Inc, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-502-0510 has 1 manufacturer part number on file: P10857A (Trac Regulator Co., Inc. Dba Trac Regulator Co Inc).
2 possible matches (shared part number, not a government interchangeability claim): 4820-01-502-0525, 4820-01-502-0533. Verify interchangeability with system specifications before substitution.
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.