The Periscope Subassembly, cataloged under National Stock Number 1240-01-347-7979, is classified within Federal Supply Class 1240 (Optical Sighting and Ranging Equipment) of the Fire Control Equipment group. The manufacturer of record is Naval Inventory Control Point Mechanicsburg. Government technical data includes 3 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 1240-01-347-7979 |
| Primary Part Number | L8821101SS |
| Item Name | Periscope Subassembly |
| FSC / FSG | 1240 / 12 — Optical Sighting and Ranging Equipment |
| Manufacturer | Naval Inventory Control Point Mechanicsburg |
| Status | ACTIVE |
| Major Components | ACTUATOR BODY 1; CYLINDER BODY 1;RETAINER 4; RING 4; PREFORMED PACKING 4 |
| Criticality Code Justification | ZZZY |
| Reference Number Differentiating Characteristics | QUALITY CONTROL IAW NAVSHIPS 0948-045-7010 MATERIAL IDENTIFICATION AND CONTROL INSTRUCTION FOR LEVEL 1 ITEMS |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL D — Destroy Item |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | S |
| Part Number | Manufacturer |
|---|---|
| L8821101SS | Naval Inventory Control Point Mechanicsburg (USA) |
| 522 6640218 REV-ITEM 01L1 | Naval Inventory Control Point Mechanicsburg (USA) |
| Reference | Meaning |
|---|---|
| 522 6640218 REV-ITEM 01 | 5/1 Secondary reference Naval Sea Systems Command |
| L8821101 | 3/9 Design control — primary reference Naval Ship Engineering Center Philadelphia Division Submarine Antenna Quality Assurance |
NSN 1240-01-347-7979 is a Periscope Subassembly, manufactured by Naval Inventory Control Point Mechanicsburg, classified under FSC 1240, Optical Sighting and Ranging Equipment. Status: active.
NSN 1240-01-347-7979 has 2 manufacturer part numbers on file: L8821101SS (Naval Inventory Control Point Mechanicsburg), 522 6640218 REV-ITEM 01L1 (Naval Inventory Control Point Mechanicsburg).
Key specifications for L8821101SS: Major Components: ACTUATOR BODY 1; CYLINDER BODY 1;RETAINER 4; RING 4; PREFORMED PACKING 4; Criticality Code Justification: ZZZY; Reference Number Differentiating Characteristics: QUALITY CONTROL IAW NAVSHIPS 0948-045-7010 MATERIAL IDENTIFICATION AND CONTROL INSTRUCTION FOR LEVEL 1 ITEMS. 3 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 1240-01-347-7979 has DEMIL Code D. 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.