The Enclosure,electromagnetic Shield, cataloged under National Stock Number 4940-01-109-6557, is classified within Federal Supply Class 4940 (Miscellaneous Maintenance and Repair Shop Specialized Equipment) of the Maintenance and Repair Shop Equipment group. The manufacturer of record is Telemechanics Inc. Government technical data includes 1 specification, 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 4940-01-109-6557 |
| Primary Part Number | 405821 |
| Item Name | Enclosure,electromagnetic Shield |
| FSC / FSG | 4940 / 49 — Miscellaneous Maintenance and Repair Shop Specialized Equipment |
| Manufacturer | Telemechanics Inc |
| Status | ACTIVE |
| General Characteristics Item Description | COPPER ALLOY; OVERALL HEIGHT 5.875 IN; DEPTH 5.188 IN; WIDTH 6.438 IN IN |
| 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 |
|---|---|
| 405821 PRIMARY | Telemechanics Inc (USA) |
| Reference | Meaning |
|---|---|
| 405821 | 5/9 Secondary reference American Telephone and Telegraph Co |
NSN 4940-01-109-6557 is a Enclosure,electromagnetic Shield, manufactured by Telemechanics Inc, classified under FSC 4940, Miscellaneous Maintenance and Repair Shop Specialized Equipment. Status: active.
NSN 4940-01-109-6557 has 1 manufacturer part number on file: 405821 (Telemechanics Inc).
1 possible match (shared part number, not a government interchangeability claim): 5365-01-370-8330. Verify interchangeability with system specifications before substitution.
Key specifications for 405821: General Characteristics Item Description: COPPER ALLOY; OVERALL HEIGHT 5.875 IN; DEPTH 5.188 IN; WIDTH 6.438 IN IN. 1 specification is 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.