The Ring,retaining,optical Element, cataloged under National Stock Number 1240-01-172-2121, is classified within Federal Supply Class 1240 (Optical Sighting and Ranging Equipment) of the Fire Control Equipment group. The manufacturer of record is Marine Corps Systems Command Div Marine Corps Systems Command Technical Data Repository Customer Service. Government technical data includes 5 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 1240-01-172-2121 |
| Primary Part Number | 82A5027A1506 |
| Item Name | Ring,retaining,optical Element |
| FSC / FSG | 1240 / 12 — Optical Sighting and Ranging Equipment |
| Manufacturer | Marine Corps Systems Command Div Marine Corps Systems Command Technical Data Repository Customer Service |
| Status | ACTIVE |
| Internal Flange Thickness | 1.27 MILLIMETERS NOMINAL MM |
| Outside Diameter | 31.63 MILLIMETERS MINIMUM AND 31.87 MILLIMETERS MAXIMUM MM |
| Aperture Diameter | 12.5 MILLIMETERS MINIMUM AND 12.9 MILLIMETERS MAXIMUM MM |
| Mounting Configuration | TWO HOLES ON 25.2 MM MINIMUM AND 25.6 MM MAXIMUM CIRCLE,3.0 MM MINIMUM AND 4.0 MM MAXIMUM DIA MM |
| Material | ALUMINUM ALLOY A413.0 |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL D — Destroy Item |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| 82A5027A1506 PRIMARY | Marine Corps Systems Command Div Marine Corps Systems Command Technical Data Repository Customer Service (USA) |
| Reference | Meaning |
|---|---|
| 82A5027A1506 | 5/9 Secondary reference L3 Technologies, Inc. Dba Insight Technology Division Div Insight Technology Division |
NSN 1240-01-172-2121 is a Ring,retaining,optical Element, manufactured by Marine Corps Systems Command Div Marine Corps Systems Command Technical Data Repository Customer Service, classified under FSC 1240, Optical Sighting and Ranging Equipment. Status: active.
NSN 1240-01-172-2121 has 1 manufacturer part number on file: 82A5027A1506 (Marine Corps Systems Command Div Marine Corps Systems Command Technical Data Repository Customer Service).
Key specifications for 82A5027A1506: Internal Flange Thickness: 1.27 MILLIMETERS NOMINAL MM; Overall Length: 7.63 MILLIMETERS MINIMUM AND 7.87 MILLIMETERS MAXIMUM MM; Outside Diameter: 31.63 MILLIMETERS MINIMUM AND 31.87 MILLIMETERS MAXIMUM MM; Aperture Diameter: 12.5 MILLIMETERS MINIMUM AND 12.9 MILLIMETERS MAXIMUM MM. 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.
NSN 1240-01-172-2121 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.