PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

P4-2Piston,pump

Star Hydraulics Llc · NSN 4320-00-122-0623 · FSC 4320 · No Item Name Available
Verified by PartsTable
NSN 4320-00-122-0623 — this item is cataloged by the U.S. Government under National Stock Number 4320-00-122-0623. Primary manufacturer part number: P4-2.
Features
  • Piston,pump — FSC 4320
  • Pinhole Diameter: 0.500 INCHES NOMINAL IN
  • Ring: NOT INCLUDED
  • Pin: NOT INCLUDED
  • Skirt Bottom Cutaway Feature: NOT INCLUDED
  • Material: STEEL
  • Distance From Pin Hole Center to Extreme Top: 0.500 INCHES NOMINAL IN
  • Pin Hole Bushing: NOT INCLUDED
Applications
  • Fluid transfer and circulation
  • Cooling system maintenance
  • Industrial process pumping
  • Applications requiring Steel construction
General Description

The Piston,pump, cataloged under National Stock Number 4320-00-122-0623, is classified within Federal Supply Class 4320 (No Item Name Available) of the Pumps and Compressors group. The primary manufacturer of record is Star Hydraulics Llc. Government technical data includes 17 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 6 commercial cross-references from 5 manufacturers, enabling identification through both NSN and commercial part number lookups. 8 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN4320-00-122-0623
Primary Part NumberP4-2
Item NamePiston,pump
FSC / FSG4320 / 43 — No Item Name Available
ManufacturerStar Hydraulics Llc
StatusACTIVE
Pinhole Diameter0.500 INCHES NOMINAL IN
RingNOT INCLUDED
PinNOT INCLUDED
Skirt Bottom Cutaway FeatureNOT INCLUDED
MaterialSTEEL
Distance From Pin Hole Center to Extreme Top0.500 INCHES NOMINAL IN
Pin Hole BushingNOT INCLUDED
Finished Size DesignationSTANDARD
Retaining Ring GrooveNOT INCLUDED
Head StyleCONCAVE
Diameter1.250 INCHES NOMINAL IN
Oil GrooveNOT INCLUDED
Distance Between Pin Bosses0.531 INCHES NOMINAL IN
Pin Type for Which DesignedFLOATING
Surface FinishFINISHED
Skirt TypeSOLID
Integral Connecting RodNOT INCLUDED
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 8
5340-00-200-8637P42 INTERCHANGEABLE
Plug,protective,dust and Moistur
Meritor Industrial Products, Llc
5306-00-208-3075P42 INTERCHANGEABLE
Bolt,internal Wrenching
Eaton Aerospace, Llc Dba Jackson South
6625-00-865-6643 INTERCHANGEABLE
Lead,test
5935-01-021-1042NG0-092120-0004 INTERCHANGEABLE
Socket,plug-in Electronic Compon
Nec America Inc
4730-01-521-8312P42 INTERCHANGEABLE
Plug,pipe
Meritor Heavy Vehicle Systems, Llc
2910-01-524-2734P-42 INTERCHANGEABLE
Pump,hand,fuel Pump
Simplex Manufacturing Co. Dba Dart Aerospace
6525-01-583-0756P4-2 INTERCHANGEABLE
Probe,ultrasonic Unit,diagnostic
Siemens Medical Solutions Usa, Inc. Dba Siemens Medical Solutions Usa Inc Div Siemens Healthineers
4320-01-695-4759P42 INTERCHANGEABLE
Pump,hydraulic Ram,hand Driven
Enerpac Tool Group Corp
Cross-Reference Index
Part NumberManufacturer
7HA953 Oshkosh Defense Llc (USA)
7HA953 Oshkosh Corp (USA)
P4-2 Amz Alabama Inc. (USA)
2HG423 Oshkosh Corp (USA)
P4-2 Bae Systems Tactical Vehicle Systems Lp Dba Data Systems International Inc (USA)
P4-2 PRIMARY Star Hydraulics Llc (USA)
Related Parts
5340-00-200-8637INTERCHANGEABLE
PLUG,PROTECTIVE,DUST AND MOISTUR
P42
5306-00-208-3075INTERCHANGEABLE
BOLT,INTERNAL WRENCHING
P42
6625-00-865-6643INTERCHANGEABLE
LEAD,TEST
5935-01-021-1042INTERCHANGEABLE
SOCKET,PLUG-IN ELECTRONIC COMPON
NG0-092120-0004
4730-01-521-8312INTERCHANGEABLE
PLUG,PIPE
P42
2910-01-524-2734INTERCHANGEABLE
PUMP,HAND,FUEL PUMP
P-42
6525-01-583-0756INTERCHANGEABLE
PROBE,ULTRASONIC UNIT,DIAGNOSTIC
P4-2
4320-01-695-4759INTERCHANGEABLE
PUMP,HYDRAULIC RAM,HAND DRIVEN
P42

Frequently Asked Questions

What is NSN 4320-00-122-0623?

NSN 4320-00-122-0623 is a Piston,pump, manufactured by Star Hydraulics Llc, classified under FSC 4320 (No Item Name Available). Status: active.

What are the part numbers for NSN 4320-00-122-0623?

NSN 4320-00-122-0623 has 6 cross-referenced part numbers: 7HA953 (Oshkosh Defense Llc), 7HA953 (Oshkosh Corp), P4-2 (Amz Alabama Inc.), 2HG423 (Oshkosh Corp), P4-2 (Bae Systems Tactical Vehicle Systems Lp Dba Data Systems International Inc) and 1 more.

What NSN replaces 4320-00-122-0623?

There are 8 known substitutes for 4320-00-122-0623: 5340-00-200-8637, 5306-00-208-3075, 6625-00-865-6643 and 5 more. Verify interchangeability with system specifications before substitution.

What are the specifications of P4-2?

Key specifications for P4-2: Pinhole Diameter: 0.500 INCHES NOMINAL IN; Ring: NOT INCLUDED; Pin: NOT INCLUDED; Skirt Bottom Cutaway Feature: NOT INCLUDED. 19 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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