PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

665-6Cartridge,check Valve

Admiral Valve Llc Dba Cpv Manufacturing · NSN 4820-00-450-9840 · FSC 4820 · No Item Name Available
Verified by PartsTable
NSN 4820-00-450-9840 — this item is cataloged by the U.S. Government under National Stock Number 4820-00-450-9840. Primary manufacturer part number: 665-6.
Features
  • Cartridge,check Valve — FSC 4820
  • Port Diameter: 1.000 INCHES NOMINAL IN
  • Thread Size and Series/type Designator: 1 1/4-11 1/2 NPT
  • Maximum Operating Temp: 225.0 FAHRENHEIT DEGF
  • Operating Pressure: 6000.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM LBS
  • Valve Size: 1.250 INCHES IN
  • Material: COPPER ALLOY
  • 3 verified cross-references
Applications
  • Flow control in piping systems
  • Pressure regulation
  • Steam and fluid isolation
  • Applications requiring Copper Alloy construction
General Description

The Cartridge,check Valve, cataloged under National Stock Number 4820-00-450-9840, is classified within Federal Supply Class 4820 (No Item Name Available) of the Valves group. The primary manufacturer of record is Admiral Valve Llc Dba Cpv Manufacturing. Government technical data includes 6 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 3 commercial cross-references from 3 manufacturers, enabling identification through both NSN and commercial part number lookups. 10 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN4820-00-450-9840
Primary Part Number665-6
Item NameCartridge,check Valve
FSC / FSG4820 / 48 — No Item Name Available
ManufacturerAdmiral Valve Llc Dba Cpv Manufacturing
StatusACTIVE
Port Diameter1.000 INCHES NOMINAL IN
Thread Size and Series/type Designator1 1/4-11 1/2 NPT
Maximum Operating Temp225.0 FAHRENHEIT DEGF
Operating Pressure6000.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM LBS
Valve Size1.250 INCHES IN
MaterialCOPPER ALLOY
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 10
5133-00-061-628844476 INTERCHANGEABLE
Drill,twist
Greenfield Industries Inc
3120-00-237-76826656 INTERCHANGEABLE
Bearing,sleeve
Quincy Compressor Division of Coltec Industries Inc Dba Quincy Compressor Div Quincy Compressor
4940-00-318-9078 INTERCHANGEABLE
Adapter
5330-00-556-7134 INTERCHANGEABLE
Packing Material
4820-00-690-20686656 INTERCHANGEABLE
Diaphragm,valve,flat
Imi Cash Valve Inc
5950-00-813-8352SM-D-415301 INTERCHANGEABLE
Transformer,audio Frequency
Us Army Communications & Electronics Materiel Readiness Command Logistics Engineering Dir
5950-00-947-6643 INTERCHANGEABLE
Coil,radio Frequency
4320-01-037-4793622/6656 INTERCHANGEABLE
Diaphragm Assembly
Coffin Turbo Pump Inc
5330-01-295-68296656 INTERCHANGEABLE
Retainer,packing
Davis Frank T and Associates
4820-01-438-15586290-G501 INTERCHANGEABLE
Cock,poppet Drain
Howell Laboratories Inc Dba Howell Laboratories Inc
Cross-Reference Index
Part NumberManufacturer
516-1929544 PIECE 9 Naval Ship Systems Command (USA)
58320-1 Mckiernan-Terry Marine Div of Litton Systems Inc (USA)
665-6 PRIMARY Admiral Valve Llc Dba Cpv Manufacturing (USA)
Related Parts
5133-00-061-6288INTERCHANGEABLE
DRILL,TWIST
44476
3120-00-237-7682INTERCHANGEABLE
BEARING,SLEEVE
6656
4940-00-318-9078INTERCHANGEABLE
ADAPTER
5330-00-556-7134INTERCHANGEABLE
PACKING MATERIAL
4820-00-690-2068INTERCHANGEABLE
DIAPHRAGM,VALVE,FLAT
6656
5950-00-813-8352INTERCHANGEABLE
TRANSFORMER,AUDIO FREQUENCY
SM-D-415301
5950-00-947-6643INTERCHANGEABLE
COIL,RADIO FREQUENCY
4320-01-037-4793INTERCHANGEABLE
DIAPHRAGM ASSEMBLY
622/6656
5330-01-295-6829INTERCHANGEABLE
RETAINER,PACKING
6656
4820-01-438-1558INTERCHANGEABLE
COCK,POPPET DRAIN
6290-G501

Frequently Asked Questions

What is NSN 4820-00-450-9840?

NSN 4820-00-450-9840 is a Cartridge,check Valve, manufactured by Admiral Valve Llc Dba Cpv Manufacturing, classified under FSC 4820 (No Item Name Available). Status: active.

What are the part numbers for NSN 4820-00-450-9840?

NSN 4820-00-450-9840 has 3 cross-referenced part numbers: 516-1929544 PIECE 9 (Naval Ship Systems Command), 58320-1 (Mckiernan-Terry Marine Div of Litton Systems Inc), 665-6 (Admiral Valve Llc Dba Cpv Manufacturing).

What NSN replaces 4820-00-450-9840?

There are 10 known substitutes for 4820-00-450-9840: 5133-00-061-6288, 3120-00-237-7682, 4940-00-318-9078 and 7 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 665-6?

Key specifications for 665-6: Port Diameter: 1.000 INCHES NOMINAL IN; Thread Size and Series/type Designator: 1 1/4-11 1/2 NPT; Maximum Operating Temp: 225.0 FAHRENHEIT DEGF; Operating Pressure: 6000.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM LBS. 6 total characteristics are documented in the Federal Logistics Information System.

Validated with multiple authoritative sources, including Government, OEM, and Certified sources.
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