The Perimeter,ophthalmic, cataloged under National Stock Number 6540-01-182-3921, is classified within Federal Supply Class 6540 (Ophthalmic Instruments, Equipment, and Supplies) of the Medical, Dental, and Veterinary Equipment group. The manufacturer of record is Defense Medical Standardization Board. Government technical data includes 2 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. Unit of issue: EA.
| Item Name | Perimeter,ophthalmic |
| FSC / FSG | 6540 — Ophthalmic Instruments, Equipment, and Supplies (FSG 65) |
| Manufacturers | Defense Medical Standardization Board (CAGE 64616) |
| Parameter | Value |
|---|---|
| NSN | 6540-01-182-3921 |
| Primary Part Number | 4-316-P |
| Item Name | Perimeter,ophthalmic |
| FSC / FSG | 6540 / 65 — Ophthalmic Instruments, Equipment, and Supplies |
| Manufacturer | Defense Medical Standardization Board |
| Status | ACTIVE |
| Current Type | AC |
| Design Designation | GOLDMAN |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Unit of Issue | EA |
| Part Number | Manufacturer |
|---|---|
| 4-316-P PRIMARY | Defense Medical Standardization Board (USA) |
NSN 6540-01-182-3921 is a Perimeter,ophthalmic, manufactured by Defense Medical Standardization Board, classified under FSC 6540, Ophthalmic Instruments, Equipment, and Supplies. Status: active.
NSN 6540-01-182-3921 has 1 manufacturer part number on file: 4-316-P (Defense Medical Standardization Board).
1 possible match (shared part number, not a government interchangeability claim): 5340-01-219-5258. Verify interchangeability with system specifications before substitution.
Key specifications for 4-316-P: Current Type: AC; Design Designation: GOLDMAN; Special Features: 120/230 VOLTS 50/60 HZ; UTILIZES SPHERICAL PROJECTION TO PROVIDE DIRECT REGISTRATION OF ABSOLUTE TARGET BRIGHTNESS OF 31.5 ASB MAXIMUM AND SPHERE LUMINOSITY OF 1000 ASB MAXIMUM ON A 30 CM RADIUS PROJECTION HEMISPHERE SURFACE; SPRING-BALANCED,CENTER POSTED TABLE,WITH PRECISE BALANCE FOR INSTRUMENT WEIGHT; CONTAINS A TELESCOPE WITH MAGNIFICATION NOT LESS THAN 1.85X; ADJUSTABLE TARGET SIZES OF 64,16,4,1/4 AND 1/16 SQ MM WITH MINIMUM THREE BUILT-IN GRAY FLILTERS HAVING RELATIVE LIGHT INTENSITY LEVELS RANGED FROM 0.0315 TO 1.00; THREE FILTER CAPS ATTACHMENT WITH RED,GREEN AND BLUE COLOR EACH; CHIN ADJUSTMENT RANGE: VERTICALLY-IN EXCESS OF 80 MM MM; Part Name Assigned by Controlling Agency: PERIMETER OPHTHALMIC:. 2 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.