The Trap,air, cataloged under National Stock Number 4730-00-905-4337, 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 17 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 4730-00-905-4337 |
| Primary Part Number | 21 |
| 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 |
| Outlet Connection Type and Quantity | 1 THREADED INTERNAL PIPE |
| Inlet Connection Nominal Pipe Size | 0.750 INCHES IN |
| Outlet Connection Nominal Pipe Size | 0.750 INCHES IN |
| Outlet Thread Direction | RIGHT-HAND |
| Outlet Thread Series Designator | NPT |
| Operating Pressure | 150.0 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 |
| Inlet Connection Type and Quantity | 1 THREADED INTERNAL PIPE |
| Material | STEEL CORROSION RESISTING FLOAT ARM |
| Material | STEEL CORROSION RESISTING BODY |
| Material | STEEL CORROSION RESISTING VALVE |
| Material | STEEL CORROSION RESISTING FLOAT |
| Inlet Thread Quantity Per Inch | 14 |
| Reference Number Differentiating Characteristics | AWNW,AWTL |
| 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 |
|---|---|
| 21 | Armstrong International Inc Dba Armstrong Machine Works (USA) |
| Reference | Meaning |
|---|---|
| 21 3/32IN ORF. | 3/1 Design control — primary reference Armstrong International Inc Dba Armstrong Machine Works |
NSN 4730-00-905-4337 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 4730-00-905-4337 has 1 manufacturer part number on file: 21 (Armstrong International Inc Dba Armstrong Machine Works).
Key specifications for 21: Outlet Connection Type and Quantity: 1 THREADED INTERNAL PIPE; Overall Height: 5.250 INCHES NOMINAL IN; Inlet Connection Nominal Pipe Size: 0.750 INCHES IN; Outlet Connection Nominal Pipe Size: 0.750 INCHES IN. 17 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.