PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

9D 1-2INValve,check

Watts Regulator Company · NSN 4820-00-422-9494 · FSC 4820 · No Item Name Available
Verified by PartsTable
NSN 4820-00-422-9494 — this item is cataloged by the U.S. Government under National Stock Number 4820-00-422-9494. Primary manufacturer part number: 9D 1-2IN.
Features
  • Valve,check — FSC 4820
  • Connection Style: PLAIN, OPTIONAL END (PIPE) ALL ENDS
  • Operating Pressure: 175.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS
  • Flow Control Device: DISK
  • Media for Which Designed: WATER, FRESH SINGLE RESPONSE
  • Connection Type: THREADED INTERNAL PIPE ALL ENDS
  • Style Designator: STRAIGHT THRU
  • Valve Operation Method: AUTOMATIC
Applications
  • Flow control in piping systems
  • Pressure regulation
  • Steam and fluid isolation
  • Applications requiring Copper Alloy Body construction
General Description

The Valve,check, cataloged under National Stock Number 4820-00-422-9494, is classified within Federal Supply Class 4820 (No Item Name Available) of the Valves group. The primary manufacturer of record is Watts Regulator Company. Government technical data includes 14 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 7 commercial cross-references from 4 manufacturers, enabling identification through both NSN and commercial part number lookups. 4 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN4820-00-422-9494
Primary Part Number9D 1-2IN
Item NameValve,check
FSC / FSG4820 / 48 — No Item Name Available
ManufacturerWatts Regulator Company
StatusACTIVE
Connection StylePLAIN, OPTIONAL END (PIPE) ALL ENDS
Operating Pressure175.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS
Flow Control DeviceDISK
Media for Which DesignedWATER, FRESH SINGLE RESPONSE
Connection TypeTHREADED INTERNAL PIPE ALL ENDS
Style DesignatorSTRAIGHT THRU
Valve Operation MethodAUTOMATIC
Thread DirectionRIGHT-HAND ALL ENDS
MaterialCOPPER ALLOY BODY
MaterialRUBBER FLOW CONTROL DEVICE
Mounting PositionHORIZONTAL
Thread Series DesignatorNPT ALL ENDS
Nominal Thread Size0.500 INCHES ALL ENDS IN
Maximum Operating Temp250.0 FAHRENHEIT SINGLE RESPONSE DEGF
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 4
5965-00-170-52358109929 INTERCHANGEABLE
Microphone,dynamic
Us Army Aviation and Missile Command
5961-00-520-84349D INTERCHANGEABLE
Transistor
Lucent Technologies Inc Corporate Headquarters
5935-01-271-1759G2804L2226B INTERCHANGEABLE
Backshell,electrical Connector
Glenair, Inc.
4820-01-294-60059D-3/4 INTERCHANGEABLE
Valve,back Flow
Watts Regulator Company
Cross-Reference Index
Part NumberManufacturer
9D Lewis Corp (USA)
6091308-2 Lockheed Martin Corporation Div Rms - Manassas (USA)
9D Teledyne Western Wire and Cable Teledyne Industries Inc (USA)
W-9D 1/2 Watts Regulator Company (USA)
9D Watts Regulator Company (USA)
9D 1-2IN PRIMARY Watts Regulator Company (USA)
9 Watts Regulator Company (USA)
Related Parts
5965-00-170-5235INTERCHANGEABLE
MICROPHONE,DYNAMIC
8109929
5961-00-520-8434INTERCHANGEABLE
TRANSISTOR
9D
5935-01-271-1759INTERCHANGEABLE
BACKSHELL,ELECTRICAL CONNECTOR
G2804L2226B
4820-01-294-6005INTERCHANGEABLE
VALVE,BACK FLOW
9D-3/4

Frequently Asked Questions

What is NSN 4820-00-422-9494?

NSN 4820-00-422-9494 is a Valve,check, manufactured by Watts Regulator Company, classified under FSC 4820 (No Item Name Available). Status: active.

What are the part numbers for NSN 4820-00-422-9494?

NSN 4820-00-422-9494 has 7 cross-referenced part numbers: 9D (Lewis Corp), 6091308-2 (Lockheed Martin Corporation Div Rms - Manassas), 9D (Teledyne Western Wire and Cable Teledyne Industries Inc), W-9D 1/2 (Watts Regulator Company), 9D (Watts Regulator Company) and 2 more.

What NSN replaces 4820-00-422-9494?

There are 4 known substitutes for 4820-00-422-9494: 5965-00-170-5235, 5961-00-520-8434, 5935-01-271-1759 and 1 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 9D 1-2IN?

Key specifications for 9D 1-2IN: Connection Style: PLAIN, OPTIONAL END (PIPE) ALL ENDS; Operating Pressure: 175.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS; Flow Control Device: DISK; Media for Which Designed: WATER, FRESH SINGLE RESPONSE. 15 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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