The Hose,air Duct, cataloged under National Stock Number 4720-01-184-5476, is classified within Federal Supply Class 4720 (Hose and Flexible Tubing) of the Pipe, Tubing, Hose, and Fittings group. The manufacturer of record is Rsa Engineered Products, Llc Dba Rsa Engineered Products Llc. Government technical data includes 14 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 4720-01-184-5476 |
| Primary Part Number | 21A18-09C28-6 |
| Item Name | Hose,air Duct |
| FSC / FSG | 4720 / 47 — Hose and Flexible Tubing |
| Manufacturer | Rsa Engineered Products, Llc Dba Rsa Engineered Products Llc |
| Status | ACTIVE |
| Measuring Method and Length | 7.000 INCHES NOMINAL OVERALL IN |
| Minimum Inside Bending Radius | 2.250 INCHES IN |
| Connection Style | ROUND FIRST END |
| Connection Type | SOFT FIRST END |
| Style Designator | FULLY CONVOLUTED W/ WIRE RINGS BETWEEN CONVOLUTIONS |
| Cross-Sectional Shape Style | ROUND |
| Wall Thickness | 0.062 INCHES NOMINAL IN |
| Operating Pressure | 35.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM LBS |
| Features Provided | OZONE RESISTANT |
| Inside Diameter | 2.250 INCHES NOMINAL FIRST END IN |
| End Overall Length | 1.500 INCHES NOMINAL FIRST END IN |
| End Inside Diameter | 2.250 INCHES NOMINAL FIRST END IN |
| Material | FIBERGLASS AND RUBBER SILICONE CLASS Q FIRST PLY |
| Material | STEEL SECOND PLY |
| 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 |
|---|---|
| 21A18-09C28-6 PRIMARY | Rsa Engineered Products, Llc Dba Rsa Engineered Products Llc (USA) |
| LE271-0109-0616 | The Boeing Company Div Legacy Am&m (USA) |
| Reference | Meaning |
|---|---|
| LE271-0109 | D/9 Drawing number reference only The Boeing Company Div Legacy Am&m |
NSN 4720-01-184-5476 is a Hose,air Duct, manufactured by Rsa Engineered Products, Llc Dba Rsa Engineered Products Llc, classified under FSC 4720, Hose and Flexible Tubing. Status: active.
NSN 4720-01-184-5476 has 2 manufacturer part numbers on file: 21A18-09C28-6 (Rsa Engineered Products, Llc Dba Rsa Engineered Products Llc), LE271-0109-0616 (The Boeing Company Div Legacy Am&m).
1 possible match (shared part number, not a government interchangeability claim): 4720-01-199-6583. Verify interchangeability with system specifications before substitution.
Key specifications for 21A18-09C28-6: Measuring Method and Length: 7.000 INCHES NOMINAL OVERALL IN; Minimum Inside Bending Radius: 2.250 INCHES IN; Connection Style: ROUND FIRST END; Connection Type: SOFT FIRST END. 14 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.