The Cover Nut, cataloged under National Stock Number 4820-01-237-9551, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Naval Inventory Control Point Mechanicsburg. Government technical data includes 3 specifications, cited from the U.S. Government catalog. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-237-9551 |
| Primary Part Number | D3791 ITEM 14 1/2 INL1 |
| Item Name | Cover Nut |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Naval Inventory Control Point Mechanicsburg |
| Status | ACTIVE |
| General Characteristics Item Description | OVERALL DIAMETER 3.250 IN.,OVERALL HEIGHT 0.937 IN.,2.687-12 UNS-2B THD. BY 0.437 IN. LONG,1.562 IN. DIA.TH RU HOLE,4 GROVES 0.375 IN. WIDE BY 0.125 IN. DEEP EQUALLY SPACED IN |
| Criticality Code Justification | ZZZY |
| Reference Number Differentiating Characteristics | QUALITY CONTROL IAW NAVSHIPS 0948-045-7010 MATERIAL IDENTIFICATION AND CONTROL INSTRUCTION FOR LEVEL 1 ITEMS |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | S |
| Part Number | Manufacturer |
|---|---|
| D3791 ITEM 14 1/2 INL1 | Naval Inventory Control Point Mechanicsburg (USA) |
| Reference | Meaning |
|---|---|
| D3791 ITEM 14 1/2 IN | 3/1 Design control — primary reference Naval Sea Systems Command Logistics Support Engineering Activity |
NSN 4820-01-237-9551 is a Cover Nut, manufactured by Naval Inventory Control Point Mechanicsburg, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-237-9551 has 1 manufacturer part number on file: D3791 ITEM 14 1/2 INL1 (Naval Inventory Control Point Mechanicsburg).
Key specifications for D3791 ITEM 14 1/2 INL1: General Characteristics Item Description: OVERALL DIAMETER 3.250 IN.,OVERALL HEIGHT 0.937 IN.,2.687-12 UNS-2B THD. BY 0.437 IN. LONG,1.562 IN. DIA.TH RU HOLE,4 GROVES 0.375 IN. WIDE BY 0.125 IN. DEEP EQUALLY SPACED IN; Criticality Code Justification: ZZZY; Reference Number Differentiating Characteristics: QUALITY CONTROL IAW NAVSHIPS 0948-045-7010 MATERIAL IDENTIFICATION AND CONTROL INSTRUCTION FOR LEVEL 1 ITEMS. 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.
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.