The Ring,retaining,optical Element, cataloged under National Stock Number 1240-00-520-4660, is classified within Federal Supply Class 1240 (Optical Sighting and Ranging Equipment) of the Fire Control Equipment group. The manufacturer of record is Combat Capabilities Development Command (ccdc) Armaments Center Dba Ccdc Div Logistics Research and Engineering Directorate. Government technical data includes 9 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 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 | 1240-00-520-4660 |
| Primary Part Number | 5204660 |
| Item Name | Ring,retaining,optical Element |
| FSC / FSG | 1240 / 12 — Optical Sighting and Ranging Equipment |
| Manufacturer | Combat Capabilities Development Command (ccdc) Armaments Center Dba Ccdc Div Logistics Research and Engineering Directorate |
| Status | ACTIVE |
| Groove Location | ADJACENT TO INTERNAL FLANGE |
| Internal Flange Thickness | 0.219 INCHES NOMINAL IN |
| Groove Diameter | 2.406 INCHES NOMINAL IN |
| Outside Diameter | 2.527 INCHES MINIMUM AND 2.529 INCHES MAXIMUM IN |
| Thread Location | INTERNAL |
| Aperture Diameter | 2.2619 INCHES MINIMUM AND 2.2649 INCHES MAXIMUM IN |
| Inner Groove Width | 0.062 INCHES NOMINAL IN |
| Mounting Configuration | 2.292-36NS-3B INTERNAL THEADS AROUND APERTURE NS |
| Material | STEEL CORROSION RESISTING |
| 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 |
|---|---|
| 5204660 PRIMARY | Combat Capabilities Development Command (ccdc) Armaments Center Dba Ccdc Div Logistics Research and Engineering Directorate (USA) |
NSN 1240-00-520-4660 is a Ring,retaining,optical Element, manufactured by Combat Capabilities Development Command (ccdc) Armaments Center Dba Ccdc Div Logistics Research and Engineering Directorate, classified under FSC 1240, Optical Sighting and Ranging Equipment. Status: active.
NSN 1240-00-520-4660 has 1 manufacturer part number on file: 5204660 (Combat Capabilities Development Command (ccdc) Armaments Center Dba Ccdc Div Logistics Research and Engineering Directorate).
1 possible match (shared part number, not a government interchangeability claim): 5895-01-255-2108. Verify interchangeability with system specifications before substitution.
Key specifications for 5204660: Groove Location: ADJACENT TO INTERNAL FLANGE; Internal Flange Thickness: 0.219 INCHES NOMINAL IN; Groove Diameter: 2.406 INCHES NOMINAL IN; Outside Diameter: 2.527 INCHES MINIMUM AND 2.529 INCHES MAXIMUM IN. 9 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.