PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

681-6Valve,check

Admiral Valve Llc Dba Cpv Manufacturing · NSN 4820-01-136-6538 · FSC 4820 · No Item Name Available
Verified by PartsTable
NSN 4820-01-136-6538 — this item is cataloged by the U.S. Government under National Stock Number 4820-01-136-6538. Primary manufacturer part number: 681-6.
Features
  • Valve,check — FSC 4820
  • Thread Series Designator: UNF ALL ENDS
  • Thread Direction: RIGHT-HAND ALL ENDS
  • Maximum Operating Temp: 225.0 FAHRENHEIT SINGLE RESPONSE DEGF
  • Material: NICKEL ALLOY SEAT
  • Connection Type: THREADED EXTERNAL TUBE ALL ENDS
  • Mounting Position: HORIZONTAL
  • Flow Control Device: DISK
Applications
  • Flow control in piping systems
  • Pressure regulation
  • Steam and fluid isolation
  • Applications requiring Nickel Alloy Seat construction
General Description

The Valve,check, cataloged under National Stock Number 4820-01-136-6538, 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 16 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 2 commercial cross-references from 1 manufacturer, 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
NSN4820-01-136-6538
Primary Part Number681-6
Item NameValve,check
FSC / FSG4820 / 48 — No Item Name Available
ManufacturerAdmiral Valve Llc Dba Cpv Manufacturing
StatusACTIVE
Thread Series DesignatorUNF ALL ENDS
Thread DirectionRIGHT-HAND ALL ENDS
Maximum Operating Temp225.0 FAHRENHEIT SINGLE RESPONSE DEGF
MaterialNICKEL ALLOY SEAT
Connection TypeTHREADED EXTERNAL TUBE ALL ENDS
Mounting PositionHORIZONTAL
Flow Control DeviceDISK
Thread Class2A ALL ENDS A
Valve Operation MethodAUTOMATIC
Media for Which DesignedWATER-OIL-GAS SINGLE RESPONSE
Style DesignatorANGLE
Nominal Thread Size2.750 INCHES ALL ENDS IN
Operating Pressure6000.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS
MaterialCOPPER ALLOY BODY
MaterialPLASTIC POLYAMIDE NYLON FLOW CONTROL DEVICE
Connection StylePLAIN (TUBE) ALL ENDS
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 10
5930-00-258-5453 INTERCHANGEABLE
Handle,switch
4730-00-278-2523 INTERCHANGEABLE
Clamp,hose
3415-00-364-09906816 INTERCHANGEABLE
Grinding Machine,utility
Black and Decker Us Inc
6645-00-570-0092 INTERCHANGEABLE
Timer
6910-00-809-6816800-6816 INTERCHANGEABLE
Moulage,war Wound
Nasco Healthcare Inc
5330-00-872-50546816 INTERCHANGEABLE
Seal,plain Encased
Skf Usa Inc. Dba Skf Aerospace Sealing Solutions
5960-00-878-2929 INTERCHANGEABLE
Electron Tube
6515-01-317-85056816 INTERCHANGEABLE
Tube Assembly,respiratory System
Bird Products Corp
4730-01-388-4713ST1063-16 INTERCHANGEABLE
Clamp,hose
Rtx Corporation Dba Pratt & Whitney Div Pratt &whitney
6210-01-428-42046816 INTERCHANGEABLE
Light,indicator
Edro Corporation, the Dba Edro Corp
Cross-Reference Index
Part NumberManufacturer
681-6 PRIMARY Admiral Valve Llc Dba Cpv Manufacturing (USA)
67178-1 1A25IPS Admiral Valve Llc Dba Cpv Manufacturing (USA)
Related Parts
5930-00-258-5453INTERCHANGEABLE
HANDLE,SWITCH
4730-00-278-2523INTERCHANGEABLE
CLAMP,HOSE
3415-00-364-0990INTERCHANGEABLE
GRINDING MACHINE,UTILITY
6816
6645-00-570-0092INTERCHANGEABLE
TIMER
6910-00-809-6816INTERCHANGEABLE
MOULAGE,WAR WOUND
800-6816
5330-00-872-5054INTERCHANGEABLE
SEAL,PLAIN ENCASED
6816
5960-00-878-2929INTERCHANGEABLE
ELECTRON TUBE
6515-01-317-8505INTERCHANGEABLE
TUBE ASSEMBLY,RESPIRATORY SYSTEM
6816
4730-01-388-4713INTERCHANGEABLE
CLAMP,HOSE
ST1063-16
6210-01-428-4204INTERCHANGEABLE
LIGHT,INDICATOR
6816

Frequently Asked Questions

What is NSN 4820-01-136-6538?

NSN 4820-01-136-6538 is a Valve,check, 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 4820-01-136-6538?

NSN 4820-01-136-6538 has 2 cross-referenced part numbers: 681-6 (Admiral Valve Llc Dba Cpv Manufacturing), 67178-1 1A25IPS (Admiral Valve Llc Dba Cpv Manufacturing).

What NSN replaces 4820-01-136-6538?

There are 10 known substitutes for 4820-01-136-6538: 5930-00-258-5453, 4730-00-278-2523, 3415-00-364-0990 and 7 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 681-6?

Key specifications for 681-6: Thread Series Designator: UNF ALL ENDS; Thread Direction: RIGHT-HAND ALL ENDS; Maximum Operating Temp: 225.0 FAHRENHEIT SINGLE RESPONSE DEGF; Material: NICKEL ALLOY SEAT. 16 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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