The Window,observation, cataloged under National Stock Number 9340-01-164-5252, is classified within Federal Supply Class 9340 (Glass Fabricated Materials) of the Nonmetallic Fabricated Materials group. The manufacturer of record is Dynalec Corporation. Government technical data includes 5 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 9340-01-164-5252 |
| Primary Part Number | 4L4 |
| Item Name | Window,observation |
| FSC / FSG | 9340 / 93 — Glass Fabricated Materials |
| Manufacturer | Dynalec Corporation |
| Status | ACTIVE |
| Overall Diameter | 4.875 INCHES NOMINAL IN |
| Overall Thickness | 0.250 INCHES NOMINAL IN |
| Material Transparency | CLEAR |
| Style Designator | CIRCULAR |
| Material | GLASS |
| 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 |
|---|---|
| 4L4 PRIMARY | Dynalec Corporation (USA) |
| MB4202-1 PC9 PRIMARY | Dynalec Corporation (USA) |
| Reference | Meaning |
|---|---|
| 4L4 | 5/9 Secondary reference The Electric Tachometer Corp. |
| MB4202-1 PC9 | 5/9 Secondary reference The Electric Tachometer Corp. |
NSN 9340-01-164-5252 is a Window,observation, manufactured by Dynalec Corporation, classified under FSC 9340, Glass Fabricated Materials. Status: active.
NSN 9340-01-164-5252 has 2 manufacturer part numbers on file: 4L4 (Dynalec Corporation), MB4202-1 PC9 (Dynalec Corporation).
Key specifications for 4L4: Overall Diameter: 4.875 INCHES NOMINAL IN; Overall Thickness: 0.250 INCHES NOMINAL IN; Material Transparency: CLEAR; Style Designator: CIRCULAR. 5 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.