The Countermeasure Aco, cataloged under National Stock Number 5845-01-413-0510, is classified within Federal Supply Class 5845 (Underwater Sound Equipment) of the Communication, Detection, and Coherent Radiation Equipment group. The manufacturer of record is Naval Sea Systems Command. Government technical data includes 10 specifications, cited from the U.S. Government catalog. The record lists 2 manufacturer part numbers 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 5845-01-413-0510 |
| Primary Part Number | MARK 4 MOD 0 |
| Item Name | Countermeasure Aco |
| FSC / FSG | 5845 / 58 — Underwater Sound Equipment |
| Manufacturer | Naval Sea Systems Command |
| Status | ACTIVE |
| Package Nominal Overall Height and Type | 18.30 INCHES SHIPPING CONTAINER IN |
| Package Nominal Overall Width and Type | 42.00 INCHES SHIPPING CONTAINER IN |
| Overall Diameter | 8.750 INCHES NOMINAL IN |
| General Characteristics Item Description | ACOUSTIC DEVICE, COUNTERMEASURE (ADC)MK 4 MOD 0 LAUNCH TUBE ASSEMBLY |
| Package Nominal Overall Length and Type | 146.00 INCHES SHIPPING CONTAINER IN |
| Hazardous Material Classification Code | 2.2 DEPARTMENT OF DEFENSE HAZARD CLASS DIVISION AND N/A FIREFIGHTING GROUP AND 00 INHABITED BUILDING DISTANCE AND S STORAGE COMPATIBILITY GROUP |
| Unable to Decode | UNABLE TO DECODE |
| Gross Weight | 2600.0 SHIPPING CONTAINER POUNDS |
| Type/model Designation | MK 4 MOD 0 |
| Reference Number Differentiating Characteristics | AS DIFFERENTIATED BY MATERIAL APPLICATION.THIS ITEM IS A COUNTERMEASURE ACOUSTIC DEVICE |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL G — Ammunition & Explosives |
| Hazard | No hazard code in the DLA record (HMIC N) 2.2 DEPARTMENT OF DEFENSE HAZARD CLASS DIVISION AND N/A FIREFIGHTING GROUP AND 00 INHABITED BUILDING DISTANCE AND S STORAGE COMPATIBILITY GROUP |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| MARK 4 MOD 0 | Naval Sea Systems Command (USA) |
| DL120575 | Naval Sea Systems Command (USA) |
| Reference | Meaning |
|---|---|
| 120575 | 3/1 Design control — primary reference U.S. Government activity |
NSN 5845-01-413-0510 is a Countermeasure Aco, manufactured by Naval Sea Systems Command, classified under FSC 5845, Underwater Sound Equipment. Status: active.
NSN 5845-01-413-0510 has 2 manufacturer part numbers on file: MARK 4 MOD 0 (Naval Sea Systems Command), DL120575 (Naval Sea Systems Command).
1 possible match (shared part number, not a government interchangeability claim): 6640-01-693-9243. Verify interchangeability with system specifications before substitution.
Key specifications for MARK 4 MOD 0: Package Nominal Overall Height and Type: 18.30 INCHES SHIPPING CONTAINER IN; Package Nominal Overall Width and Type: 42.00 INCHES SHIPPING CONTAINER IN; Overall Diameter: 8.750 INCHES NOMINAL IN; General Characteristics Item Description: ACOUSTIC DEVICE, COUNTERMEASURE (ADC)MK 4 MOD 0 LAUNCH TUBE ASSEMBLY. 10 specifications are documented in the U.S. Government catalog.
No hazard code in the DLA record (HMIC N). The government record also carries hazard data: DOT hazard class, UN number, or related classification fields. Special handling, storage, and shipping requirements apply per the cited government fields.
NSN 5845-01-413-0510 has DEMIL Code G. 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.