PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

801-01Seat,valve

Trac Regulator Co., Inc. Dba Trac Regulator Co Inc · NSN 4820-01-256-4879 · FSC 4820 · No Item Name Available
Verified by PartsTable
NSN 4820-01-256-4879 — this item is cataloged by the U.S. Government under National Stock Number 4820-01-256-4879. Primary manufacturer part number: 801-01.
Features
  • Seat,valve — FSC 4820
  • Seating Surface Shape: FLAT
  • Body Inside Diameter: 3.875 INCHES NOMINAL IN
  • Material: COPPER ALLOY BODY
  • Thread Series Designator: UN SINGLE THREADED PORTION
  • Style Designator: THREADED FLANGED
  • Thread Quantity Per Inch: 14 SINGLE THREADED PORTION
  • Thread Class: 3B SINGLE THREADED PORTION
Applications
  • Flow control in piping systems
  • Pressure regulation
  • Steam and fluid isolation
  • Applications requiring Copper Alloy Body construction
General Description

The Seat,valve, cataloged under National Stock Number 4820-01-256-4879, is classified within Federal Supply Class 4820 (No Item Name Available) of the Valves group. The primary manufacturer of record is Trac Regulator Co., Inc. Dba Trac Regulator Co Inc. Government technical data includes 12 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 1 commercial cross-reference from 1 manufacturer, enabling identification through both NSN and commercial part number lookups. 7 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN4820-01-256-4879
Primary Part Number801-01
Item NameSeat,valve
FSC / FSG4820 / 48 — No Item Name Available
ManufacturerTrac Regulator Co., Inc. Dba Trac Regulator Co Inc
StatusACTIVE
Seating Surface ShapeFLAT
Body Inside Diameter3.875 INCHES NOMINAL IN
MaterialCOPPER ALLOY BODY
Thread Series DesignatorUN SINGLE THREADED PORTION
Style DesignatorTHREADED FLANGED
Thread Quantity Per Inch14 SINGLE THREADED PORTION
Thread Class3B SINGLE THREADED PORTION
Thread Length0.875 INCHES NOMINAL SINGLE THREADED PORTION IN
Flange Seat to Disk End Height0.312 INCHES NOMINAL IN
Nominal Thread Size4.250 INCHES SINGLE THREADED PORTION IN
Flange Diameter4.375 INCHES NOMINAL IN
Under Flange Height1.000 INCHES NOMINAL IN
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 7
5961-00-880-2938 INTERCHANGEABLE
Semiconductor Device,diode
5930-01-013-05712075162-0715 INTERCHANGEABLE
Switch,code Indicating Wheel
Raytheon Company Dba Raytheon Co
4820-01-314-256180101 INTERCHANGEABLE
Parts Kit,valve
W.w. Grainger, Inc. Div Government Sales Division
6625-01-340-38448010-1 INTERCHANGEABLE
Test Set,respirator
Tsi Incorporated
7050-01-423-784980101 INTERCHANGEABLE
Converter,digital to Analog
Dynatron Systems Corporation
5310-01-567-755580101 INTERCHANGEABLE
Nut,plain,extended Washer,hexago
Hutchinson Industries, Inc Div Defense and Industry
7025-01-683-396880101 INTERCHANGEABLE
Optical Reader,data Entry
Mspt, Llc Dba Mspt Llc
Cross-Reference Index
Part NumberManufacturer
801-01 PRIMARY Trac Regulator Co., Inc. Dba Trac Regulator Co Inc (USA)
Related Parts
5961-00-880-2938INTERCHANGEABLE
SEMICONDUCTOR DEVICE,DIODE
5930-01-013-0571INTERCHANGEABLE
SWITCH,CODE INDICATING WHEEL
2075162-0715
4820-01-314-2561INTERCHANGEABLE
PARTS KIT,VALVE
80101
6625-01-340-3844INTERCHANGEABLE
TEST SET,RESPIRATOR
8010-1
7050-01-423-7849INTERCHANGEABLE
CONVERTER,DIGITAL TO ANALOG
80101
5310-01-567-7555INTERCHANGEABLE
NUT,PLAIN,EXTENDED WASHER,HEXAGO
80101
7025-01-683-3968INTERCHANGEABLE
OPTICAL READER,DATA ENTRY
80101

Frequently Asked Questions

What is NSN 4820-01-256-4879?

NSN 4820-01-256-4879 is a Seat,valve, manufactured by Trac Regulator Co., Inc. Dba Trac Regulator Co Inc, classified under FSC 4820 (No Item Name Available). Status: active.

What are the part numbers for NSN 4820-01-256-4879?

NSN 4820-01-256-4879 has 1 cross-referenced part number: 801-01 (Trac Regulator Co., Inc. Dba Trac Regulator Co Inc).

What NSN replaces 4820-01-256-4879?

There are 7 known substitutes for 4820-01-256-4879: 5961-00-880-2938, 5930-01-013-0571, 4820-01-314-2561 and 4 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 801-01?

Key specifications for 801-01: Seating Surface Shape: FLAT; Body Inside Diameter: 3.875 INCHES NOMINAL IN; Material: COPPER ALLOY BODY; Thread Series Designator: UN SINGLE THREADED PORTION. 12 total characteristics are documented in the Federal Logistics Information System.

Validated with multiple authoritative sources, including Government, OEM, and Certified sources.
PartsTable Design LLC · partstable.com