The Glass,liquid Sight Indicator,rou, cataloged under National Stock Number 6680-01-689-6600, is classified within Federal Supply Class 6680 (Liquid and Gas Flow, Liquid Level, and Mechanical Motion Measuring Instruments) of the Instruments and Laboratory Equipment group. The manufacturer of record is Hydro-Craft, Inc.. The record lists 1 manufacturer part number 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Item Name | Glass,liquid Sight Indicator,rou |
| FSC / FSG | 6680 — Liquid and Gas Flow, Liquid Level, and Mechanical Motion Measuring Instruments (FSG 66) |
| Manufacturers | Hydro-Craft, Inc. (CAGE 23619) |
| Parameter | Value |
|---|---|
| NSN | 6680-01-689-6600 |
| Primary Part Number | HC-SP-16 |
| Item Name | Glass,liquid Sight Indicator,rou |
| FSC / FSG | 6680 / 66 — Liquid and Gas Flow, Liquid Level, and Mechanical Motion Measuring Instruments |
| Manufacturer | Hydro-Craft, Inc. |
| Status | ACTIVE |
| 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 |
|---|---|
| HC-SP-16 PRIMARY | Hydro-Craft, Inc. (USA) |
| Reference | Meaning |
|---|---|
| 3596AS529-2 | 7/2 Vendor item drawing reference Naval Air Systems Command Managed Original Design Activity Not Material/parts Supplier |
| 3596AS529 | D/9 Drawing number reference only Naval Air Systems Command Managed Original Design Activity Not Material/parts Supplier |
NSN 6680-01-689-6600 is a Glass,liquid Sight Indicator,rou, manufactured by Hydro-Craft, Inc., classified under FSC 6680, Liquid and Gas Flow, Liquid Level, and Mechanical Motion Measuring Instruments. Status: active.
NSN 6680-01-689-6600 has 1 manufacturer part number on file: HC-SP-16 (Hydro-Craft, Inc.).
1 possible match (shared part number, not a government interchangeability claim): 6680-01-689-7991. Verify interchangeability with system specifications before substitution.
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.