The Bottle,top-Off,coolant System, cataloged under National Stock Number 4920-01-021-5507, is classified within Federal Supply Class 4920 (Aircraft Maintenance and Repair Shop Specialized Equipment) of the Maintenance and Repair Shop Equipment group. The manufacturer of record is Honeywell International Inc. Dba Honeywell International Div Aerospace - Tempe (west Warner Road). Government technical data includes 3 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 4920-01-021-5507 |
| Primary Part Number | 3315240 |
| Item Name | Bottle,top-Off,coolant System |
| FSC / FSG | 4920 / 49 — Aircraft Maintenance and Repair Shop Specialized Equipment |
| Manufacturer | Honeywell International Inc. Dba Honeywell International Div Aerospace - Tempe (west Warner Road) |
| Status | ACTIVE |
| Overall Diameter | 5.500 INCHES NOMINAL IN |
| Reference Data and Literature | TO 35-1-251-1 |
| Functional Description | USED IN CONJUNCTION WITH THE FC-77 TOPOFF BOTTLE HOSE AND ADAPTER, PART NUMBER 954A805G01, TO REPLACE SMALL QUANTITIES OF FC-77 FLUID WITHOUT INTRODUCING AIR INTO THE SYSTEM, AS REQUIRED BY THE THERMAL STABILIZATION SYSTEM AND AFTER REPLACEMENT OF THE THERMAL STABILIZATION UNIT FILTER DURING ORGANIZATIONAL AND DEPOT LEVEL MAINTENANCE |
| 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 |
|---|---|
| 3315240 PRIMARY | Honeywell International Inc. Dba Honeywell International Div Aerospace - Tempe (west Warner Road) (USA) |
| Reference | Meaning |
|---|---|
| 3315240 | 5/9 Secondary reference Allied-Signal Inc Dba Allied-Signal Aerospace Co Electrodynamics Div |
NSN 4920-01-021-5507 is a Bottle,top-Off,coolant System, manufactured by Honeywell International Inc. Dba Honeywell International Div Aerospace - Tempe (west Warner Road), classified under FSC 4920, Aircraft Maintenance and Repair Shop Specialized Equipment. Status: active.
NSN 4920-01-021-5507 has 1 manufacturer part number on file: 3315240 (Honeywell International Inc. Dba Honeywell International Div Aerospace - Tempe (west Warner Road)).
Key specifications for 3315240: Overall Diameter: 5.500 INCHES NOMINAL IN; Reference Data and Literature: TO 35-1-251-1; Overall Length: 9.000 INCHES NOMINAL IN; Special Features: CONSISTS OF A SPHERICAL PRESSURE VESSEL WITH A BLADDER TO SEPARATE THE FC-77 FLUID FROM THE PRESSURIZING GAS. THE ACCUMULATOR IS EQUIPPED WITH AN AIR VALVE FOR PRESSURIZING AND THREADED PORT FOR AN OUTPUT. 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.
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.