The Trap,air, cataloged under National Stock Number 4730-00-063-9832, 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 Armstrong International Inc Dba Armstrong Machine Works. Government technical data includes 13 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 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 | 4730-00-063-9832 |
| Primary Part Number | 21AR |
| Item Name | Trap,air |
| FSC / FSG | 4730 / 47 — Hose, Pipe, Tube, Lubrication, and Railing Fittings |
| Manufacturer | Armstrong International Inc Dba Armstrong Machine Works |
| Status | ACTIVE |
| Inlet Connection Nominal Pipe Size | 0.500 INCHES IN |
| Outlet Connection Nominal Pipe Size | 0.500 INCHES IN |
| Outlet Thread Series Designator | NPT |
| Operating Pressure | 175.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM LBS |
| Overall Outside Diameter | 6.250 INCHES NOMINAL IN |
| Thread Direction | RIGHT-HAND INLET |
| Inlet Thread Series Designator | NPT |
| Outlet Thread Quantity Per Inch | 14 |
| Material | STEEL CORROSION RESISTING FLOAT ARM |
| Material | STEEL CORROSION RESISTING VALVE |
| Material | IRON CAST BODY |
| Material | STEEL CORROSION RESISTING FLOAT |
| Inlet Thread Quantity Per Inch | 14 |
| 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 |
|---|---|
| 21AR PRIMARY | Armstrong International Inc Dba Armstrong Machine Works (USA) |
NSN 4730-00-063-9832 is a Trap,air, manufactured by Armstrong International Inc Dba Armstrong Machine Works, classified under FSC 4730, Hose, Pipe, Tube, Lubrication, and Railing Fittings. Status: active.
NSN 4730-00-063-9832 has 1 manufacturer part number on file: 21AR (Armstrong International Inc Dba Armstrong Machine Works).
1 possible match (shared part number, not a government interchangeability claim): 4730-00-840-1948. Verify interchangeability with system specifications before substitution.
Key specifications for 21AR: Overall Height: 5.250 INCHES NOMINAL IN; Inlet Connection Nominal Pipe Size: 0.500 INCHES IN; Outlet Connection Nominal Pipe Size: 0.500 INCHES IN; Outlet Thread Series Designator: NPT. 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.