The Fitting,special, cataloged under National Stock Number 1660-01-686-6423, is classified within Federal Supply Class 1660 (Aircraft Air Conditioning, Heating, and Pressurizing Equipment) of the Aircraft Components and Accessories group. The manufacturer of record is Harlow Aerostructures, Llc. The record lists 9 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Item Name | Fitting,special |
| FSC / FSG | 1660 — Aircraft Air Conditioning, Heating, and Pressurizing Equipment (FSG 16) |
| Manufacturers | Harlow Aerostructures, Llc (CAGE 14248); Preci-Manufacturing, Incorporated (CAGE 66841); The Boeing Company Div Defense (CAGE 76301); Forrest Machining Llc Dba Fmi Aerostructures (CAGE 0FRC8); D-J Engineering Inc Dba D-J Engineering Inc (CAGE 0C7H8) |
| Parameter | Value |
|---|---|
| NSN | 1660-01-686-6423 |
| Primary Part Number | 520-10515-501 |
| Item Name | Fitting,special |
| FSC / FSG | 1660 / 16 — Aircraft Air Conditioning, Heating, and Pressurizing Equipment |
| Manufacturer | Harlow Aerostructures, Llc |
| Status | ACTIVE |
| 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 |
|---|---|
| 520-10515-501 | Harlow Aerostructures, Llc (USA) |
| 520-10515-501 | Preci-Manufacturing, Incorporated (USA) |
| 520-10515-501 | The Boeing Company Div Defense (USA) |
| 520-10515-501 | Forrest Machining Llc Dba Fmi Aerostructures (USA) |
| 520-10515-501 | D-J Engineering Inc Dba D-J Engineering Inc (USA) |
| 520-10515-501 | Nordam Group Llc, the Div Nordam (USA) |
| 520-10515-501 | Malones Cnc Machining Inc (USA) |
| 520-10515-501 | Tect Hypervelocity, Inc. (USA) |
| 520-10515-501 | Camnetics Manufacturing Corporation (USA) |
| Reference | Meaning |
|---|---|
| 520-10515-501 | 3/2 Design control — primary reference U.S. Government activity |
NSN 1660-01-686-6423 is a Fitting,special, manufactured by Harlow Aerostructures, Llc, classified under FSC 1660, Aircraft Air Conditioning, Heating, and Pressurizing Equipment. Status: active.
NSN 1660-01-686-6423 has 9 manufacturer part numbers on file: 520-10515-501 (Harlow Aerostructures, Llc), 520-10515-501 (Preci-Manufacturing, Incorporated), 520-10515-501 (The Boeing Company Div Defense), 520-10515-501 (Forrest Machining Llc Dba Fmi Aerostructures), 520-10515-501 (D-J Engineering Inc Dba D-J Engineering Inc) and 4 more.
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.