The Nut,union, cataloged under National Stock Number 4730-00-188-7481, is classified within Federal Supply Class 4730 (Hose, Pipe, Tube, Lubrication, and Railing Fittings) of the Pipe, Tubing, Hose, and Fittings group. The manufacturer of record is Hydrasearch Company, Llc. Government technical data includes 13 specifications, cited from the U.S. Government catalog. The record lists 2 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 4 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4730-00-188-7481 |
| Primary Part Number | 6N503CS |
| Item Name | Nut,union |
| FSC / FSG | 4730 / 47 — Hose, Pipe, Tube, Lubrication, and Railing Fittings |
| Manufacturer | Hydrasearch Company, Llc |
| Status | ACTIVE |
| Width Across Flats | 2.000 INCHES NOMINAL IN |
| Shoulder Step Width | 0.250 INCHES NOMINAL IN |
| Shoulder Width | 0.312 INCHES NOMINAL IN |
| Thread Series | UN |
| Thread Direction | RIGHT-HAND |
| Nominal Thread Size | 1.750 INCHES IN |
| Nut Height | 1.062 INCHES NOMINAL IN |
| Surface Treatment | ZINC OVERALL |
| Nut Style | HEXAGON |
| Thread Quantity Per Inch | 12 |
| Material | STEEL OVERALL |
| Smallest Inside Diameter | 1.378 INCHES NOMINAL IN |
| Shoulder Seat Diameter | 1.750 INCHES NOMINAL IN |
| 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 |
|---|---|
| GS6085-17 | Hamilton Sundstrand Corporation Dba Collins Aerospace (USA) |
| 6N503CS PRIMARY | Hydrasearch Company, Llc (USA) |
| Reference | Meaning |
|---|---|
| B-4019 | D/9 Drawing number reference only U.S. Government activity |
| 50N3 | 5/9 Secondary reference U.S. Government activity |
| 50N-3-S | 3/2 Design control — primary reference U.S. Government activity |
NSN 4730-00-188-7481 is a Nut,union, manufactured by Hydrasearch Company, Llc, classified under FSC 4730, Hose, Pipe, Tube, Lubrication, and Railing Fittings. Status: active.
NSN 4730-00-188-7481 has 2 manufacturer part numbers on file: GS6085-17 (Hamilton Sundstrand Corporation Dba Collins Aerospace), 6N503CS (Hydrasearch Company, Llc).
4 possible matches (shared part number, not a government interchangeability claim): 4730-00-188-7498, 4730-01-070-7657, 4730-01-311-3921. Verify interchangeability with system specifications before substitution.
Key specifications for 6N503CS: Width Across Flats: 2.000 INCHES NOMINAL IN; Shoulder Step Width: 0.250 INCHES NOMINAL IN; Shoulder Width: 0.312 INCHES NOMINAL IN; Thread Series: UN. 13 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.