The Reducer,boss, cataloged under National Stock Number 4730-00-640-1933, 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 Sae International Dba Sae International. Government technical data includes 15 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through both NSN and commercial part number lookups. 10 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4730-00-640-1933 |
| Primary Part Number | MS21916W12-5 |
| Item Name | Reducer,boss |
| FSC / FSG | 4730 / 47 — Hose, Pipe, Tube, Lubrication, and Railing Fittings |
| Manufacturer | Sae International Dba Sae International |
| Status | ACTIVE |
| Surface Treatment Document and Classification | MIL-A-8625 MIL SPEC SINGLE TREATMENT RESPONSE OUTSIDE |
| Surface Treatment Document and Classification | MIL-A-8625 MIL SPEC SINGLE TREATMENT RESPONSE INSIDE |
| Connection Style | EXTERNAL SEAT FOR GASKET SEAL (BOSS) ALL ENDS |
| Nominal Overall Length | 1.531 INCHES IN |
| Connection Type | THREADED EXTERNAL BOSS ALL ENDS |
| Nominal Thread Size | 0.500 INCHES SECOND END IN |
| Nominal Thread Size | 1.062 INCHES FIRST END IN |
| Specification/standard Data | 81343-AS21916 PROFESSIONAL/INDUSTRIAL ASSOCIATION STANDARD |
| Surface Treatment | ANODIZE OVERALL |
| Thread Class | 3A ALL ENDS A |
| Thread Quantity Per Inch | 12 FIRST END |
| Material | ALUMINUM ALLOY OVERALL |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) SECOND END |
| Thread Series Designator | UNIFIED NATIONAL JOINT (UNJ) FIRST END |
| Reducer Type | CONCENTRIC |
| 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 |
|---|---|
| MS21916W12-5 PRIMARY | Sae International Dba Sae International (USA) |
| Reference | Meaning |
|---|---|
| ER919D12-5 | 5/9 Secondary reference Dana Corp Weatherhead Div |
| AS18280 | 5/9 Secondary reference Sae International Dba Sae International |
| AS21916 | 5/9 Secondary reference U.S. Government activity |
| MS21916D12-5 | 5/9 Secondary reference U.S. Government activity |
| SAE-AS18280 | 3/1 Design control — primary reference Sae International Dba Sae International |
| MS21916D12-5 | 5/9 Secondary reference U.S. Government activity |
| MS21912W12-5 | 5/9 Secondary reference U.S. Government activity |
| AS18280 | 5/9 Secondary reference U.S. Government activity |
| AS21916 | 5/9 Secondary reference Sae International Dba Sae International |
| MS21916W12-5 | 5/9 Secondary reference U.S. Government activity |
NSN 4730-00-640-1933 is a Reducer,boss, manufactured by Sae International Dba Sae International, classified under FSC 4730, Hose, Pipe, Tube, Lubrication, and Railing Fittings. Status: active.
NSN 4730-00-640-1933 has 1 manufacturer part number on file: MS21916W12-5 (Sae International Dba Sae International).
Key specifications for MS21916W12-5: Surface Treatment Document and Classification: MIL-A-8625 MIL SPEC SINGLE TREATMENT RESPONSE OUTSIDE; Surface Treatment Document and Classification: MIL-A-8625 MIL SPEC SINGLE TREATMENT RESPONSE INSIDE; Connection Style: EXTERNAL SEAT FOR GASKET SEAL (BOSS) ALL ENDS; Nominal Overall Length: 1.531 INCHES IN. 15 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.