PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

8988 ITEM 3Seat,valve

William E Williams Valve Corp · NSN 4820-01-311-8393 · FSC 4820 · No Item Name Available
Verified by PartsTable
NSN 4820-01-311-8393 — this item is cataloged by the U.S. Government under National Stock Number 4820-01-311-8393. Primary manufacturer part number: 8988 ITEM 3.
Features
  • Seat,valve — FSC 4820
  • Seating Surface Shape: FLAT
  • Material: STEEL SEAT
  • Style Designator: PLAIN
  • 2 verified cross-references
  • Primary manufacturer: William E Williams Valve Corp
Applications
  • Flow control in piping systems
  • Pressure regulation
  • Steam and fluid isolation
  • Applications requiring Steel Seat construction
General Description

The Seat,valve, cataloged under National Stock Number 4820-01-311-8393, is classified within Federal Supply Class 4820 (No Item Name Available) of the Valves group. The primary manufacturer of record is William E Williams Valve Corp. Government technical data includes 3 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. 6 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN4820-01-311-8393
Primary Part Number8988 ITEM 3
Item NameSeat,valve
FSC / FSG4820 / 48 — No Item Name Available
ManufacturerWilliam E Williams Valve Corp
StatusACTIVE
Seating Surface ShapeFLAT
MaterialSTEEL SEAT
Style DesignatorPLAIN
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 6
5950-00-485-76611M141-1 INTERCHANGEABLE
Transformer,power
Northrop Grumman Corp Electronic Systems Defensive System Div
5960-00-860-7710 INTERCHANGEABLE
Shield,electron Tube
5120-01-069-56878988 INTERCHANGEABLE
Alignment Tool,electronic Equipm
Gc/waldom Inc
5330-01-134-86888988 INTERCHANGEABLE
Gasket
Crane Pumps & Systems Pft Corp Div Crane Pumps & System Pft Corp.
4210-01-244-0117 INTERCHANGEABLE
Ax,pick Head
4820-01-312-68198988 ITEM 16 INTERCHANGEABLE
Stem,fluid Valve
William E Williams Valve Corp
Cross-Reference Index
Part NumberManufacturer
8988 William E Williams Valve Corp (USA)
8988 ITEM 3 PRIMARY William E Williams Valve Corp (USA)
Related Parts
5950-00-485-7661INTERCHANGEABLE
TRANSFORMER,POWER
1M141-1
5960-00-860-7710INTERCHANGEABLE
SHIELD,ELECTRON TUBE
5120-01-069-5687INTERCHANGEABLE
ALIGNMENT TOOL,ELECTRONIC EQUIPM
8988
5330-01-134-8688INTERCHANGEABLE
GASKET
8988
4210-01-244-0117INTERCHANGEABLE
AX,PICK HEAD
4820-01-312-6819INTERCHANGEABLE
STEM,FLUID VALVE
8988 ITEM 16

Frequently Asked Questions

What is NSN 4820-01-311-8393?

NSN 4820-01-311-8393 is a Seat,valve, manufactured by William E Williams Valve Corp, classified under FSC 4820 (No Item Name Available). Status: active.

What are the part numbers for NSN 4820-01-311-8393?

NSN 4820-01-311-8393 has 2 cross-referenced part numbers: 8988 (William E Williams Valve Corp), 8988 ITEM 3 (William E Williams Valve Corp).

What NSN replaces 4820-01-311-8393?

There are 6 known substitutes for 4820-01-311-8393: 5950-00-485-7661, 5960-00-860-7710, 5120-01-069-5687 and 3 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 8988 ITEM 3?

Key specifications for 8988 ITEM 3: Seating Surface Shape: FLAT; Material: STEEL SEAT; Style Designator: PLAIN. 3 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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