The Lens,optical Instrument, cataloged under National Stock Number 6650-01-339-5256, is classified within Federal Supply Class 6650 (Optical Instruments, Test Equipment, Components and Accessories) of the Instruments and Laboratory Equipment group. Government technical data includes 4 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 6650-01-339-5256 |
| Item Name | Lens,optical Instrument |
| FSC / FSG | 6650 / 66 — Optical Instruments, Test Equipment, Components and Accessories |
| Status | ACTIVE |
| Diameter | 2.195 INCHES NOMINAL IN |
| Axial Thickness | 0.075 INCHES NOMINAL IN |
| Material | GLASS |
| Single Lens Style | PLANO-CONCAVE |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL B — Remove Demilitarization Key Points |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Reference | Meaning |
|---|---|
| 34574 | 3/2 Design control — primary reference U.S. Government activity |
NSN 6650-01-339-5256 is a Lens,optical Instrument, classified under FSC 6650, Optical Instruments, Test Equipment, Components and Accessories. Status: active.
2 possible matches (shared part number, not a government interchangeability claim): 3020-01-377-6990, 5930-01-602-8273. Verify interchangeability with system specifications before substitution.
Key specifications for 6650-01-339-5256: Diameter: 2.195 INCHES NOMINAL IN; Axial Thickness: 0.075 INCHES NOMINAL IN; Special Features: 3 REFLECTING GLASS SURFACES ALONG TOP EDGE; BOTTOM AND TOP SURFACES PAINTED WITH WHITE ENAMEL; End Item Identification: H-1 HELICOPTER. 4 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.
NSN 6650-01-339-5256 has DEMIL Code B. Demilitarization may be required before disposal or transfer to non-military entities.
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.