PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

NAS4121-117BHeat Sink,electrical-Electronic

National Aerospace Standards Committee Aerospace Industries Association of America Inc Not for Rfq or Solicitation Use · NSN 5999-01-423-6866 · FSC 5999 · No Item Name Available
Verified by PartsTable
NSN 5999-01-423-6866 — this item is cataloged by the U.S. Government under National Stock Number 5999-01-423-6866. Primary manufacturer part number: NAS4121-117B.
Features
  • Heat Sink,electrical-Electronic — FSC 5999
  • Material: ALUMINUM
  • Mounting Facility Type and Quantity: 4 UNTHREADED HOLE(S) SINGLE MOUNTING FACILITY
  • Mounting Facility Type and Quantity: 2 UNTHREADED HOLE(S) FIRST MOUNTING FACILITY
  • Unthreaded Mounting Hole Diameter: 0.190 INCHES NOMINAL FIRST MOUNTING FACILITY IN
  • Unthreaded Mounting Hole Diameter: 0.220 INCHES NOMINAL SECOND MOUNTING FACILITY IN
  • Body Style: BOARD MOUNTED
  • Mounting Facility Type and Quantity: 2 UNTHREADED HOLE(S) SECOND MOUNTING FACILITY
Applications
  • Applications requiring Aluminum construction
General Description

The Heat Sink,electrical-Electronic, cataloged under National Stock Number 5999-01-423-6866, is classified within Federal Supply Class 5999 (No Item Name Available) of the Electrical and Electronic Equipment Components group. The primary manufacturer of record is National Aerospace Standards Committee Aerospace Industries Association of America Inc Not for Rfq or Solicitation Use. Government technical data includes 14 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 5 commercial cross-references from 2 manufacturers, enabling identification through both NSN and commercial part number lookups. 12 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active. Unit of issue: EA.

Technical Specifications
ParameterValue
NSN5999-01-423-6866
Primary Part NumberNAS4121-117B
Item NameHeat Sink,electrical-Electronic
FSC / FSG5999 / 59 — No Item Name Available
ManufacturerNational Aerospace Standards Committee Aerospace Industries Association of America Inc Not for Rfq or Solicitation Use
StatusACTIVE
MaterialALUMINUM
Mounting Facility Type and Quantity4 UNTHREADED HOLE(S) SINGLE MOUNTING FACILITY
Mounting Facility Type and Quantity2 UNTHREADED HOLE(S) FIRST MOUNTING FACILITY
Unthreaded Mounting Hole Diameter0.190 INCHES NOMINAL FIRST MOUNTING FACILITY IN
Unthreaded Mounting Hole Diameter0.220 INCHES NOMINAL SECOND MOUNTING FACILITY IN
Body StyleBOARD MOUNTED
Mounting Facility Type and Quantity2 UNTHREADED HOLE(S) SECOND MOUNTING FACILITY
MaterialALUMINUM
Mounting Facility Type and Quantity4 UNTHREADED HOLE(S) SINGLE MOUNTING FACILITY
Mounting Facility Type and Quantity2 UNTHREADED HOLE(S) FIRST MOUNTING FACILITY
Unthreaded Mounting Hole Diameter0.190 INCHES NOMINAL FIRST MOUNTING FACILITY IN
Unthreaded Mounting Hole Diameter0.220 INCHES NOMINAL SECOND MOUNTING FACILITY IN
Body StyleBOARD MOUNTED
Mounting Facility Type and Quantity2 UNTHREADED HOLE(S) SECOND MOUNTING FACILITY
Lifecycle & Compliance
Acquisition StatusACTIVE
Successor5999-01-137-5400
HAZMATNo
Shelf Life Code0
Unit of IssueEA
SMR CodeJ
Verified Substitutes 12
Heat Sink,electrical-Electronic
Heat Sink,electrical-Electronic
Heat Sink,electrical-Electronic
Heat Sink,electrical-Electronic
Heat Sink,electrical-Electronic
Heat Sink,electrical-Electronic
Heat Sink,electrical-Electronic
Heat Sink,electrical-Electronic
Heat Sink,electrical-Electronic
Heat Sink,electrical-Electronic
Cross-Reference Index
Part NumberManufacturer
NAS4121-117B PRIMARY National Aerospace Standards Committee Aerospace Industries Association of America Inc Not for Rfq or Solicitation Use (USA)
MIL-H-87111/5 Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M
M87111/05-1A117 Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M
NAS4121-1A117 National Aerospace Standards Committee Aerospace Industries Association of America Inc Not for Rfq or Solicitation Use (USA)
NAS4121 National Aerospace Standards Committee Aerospace Industries Association of America Inc Not for Rfq or Solicitation Use (USA)
Related Parts
SUCCESSOR 5999-01-137-5400 Heat Sink,electrical-Electronic
5999-01-205-3100SUCCESSOR
HEAT SINK,ELECTRICAL-ELECTRONIC
5999-01-209-0651SUCCESSOR
HEAT SINK,ELECTRICAL-ELECTRONIC
5999-01-209-0652SUCCESSOR
HEAT SINK,ELECTRICAL-ELECTRONIC
5999-01-209-0654SUCCESSOR
HEAT SINK,ELECTRICAL-ELECTRONIC
5999-01-209-0655SUCCESSOR
HEAT SINK,ELECTRICAL-ELECTRONIC
5999-01-209-0656SUCCESSOR
HEAT SINK,ELECTRICAL-ELECTRONIC
5999-01-209-0657SUCCESSOR
HEAT SINK,ELECTRICAL-ELECTRONIC
5999-01-209-2812SUCCESSOR
HEAT SINK,ELECTRICAL-ELECTRONIC
5999-01-209-2813SUCCESSOR
HEAT SINK,ELECTRICAL-ELECTRONIC
5999-01-209-4597SUCCESSOR
HEAT SINK,ELECTRICAL-ELECTRONIC
5999-01-210-2287SUCCESSOR
HEAT SINK,ELECTRICAL-ELECTRONIC

Frequently Asked Questions

What is NSN 5999-01-423-6866?

NSN 5999-01-423-6866 is a Heat Sink,electrical-Electronic, manufactured by National Aerospace Standards Committee Aerospace Industries Association of America Inc Not for Rfq or Solicitation Use, classified under FSC 5999 (No Item Name Available). Status: active.

What are the part numbers for NSN 5999-01-423-6866?

NSN 5999-01-423-6866 has 5 cross-referenced part numbers: NAS4121-117B (National Aerospace Standards Committee Aerospace Industries Association of America Inc Not for Rfq or Solicitation Use), MIL-H-87111/5 (Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M), M87111/05-1A117 (Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M), NAS4121-1A117 (National Aerospace Standards Committee Aerospace Industries Association of America Inc Not for Rfq or Solicitation Use), NAS4121 (National Aerospace Standards Committee Aerospace Industries Association of America Inc Not for Rfq or Solicitation Use).

What NSN replaces 5999-01-423-6866?

There are 12 known substitutes for 5999-01-423-6866: 5999-01-137-5400, 5999-01-205-3100, 5999-01-209-0651 and 9 more. Verify interchangeability with system specifications before substitution.

What are the specifications of NAS4121-117B?

Key specifications for NAS4121-117B: Material: ALUMINUM; Mounting Facility Type and Quantity: 4 UNTHREADED HOLE(S) SINGLE MOUNTING FACILITY; Mounting Facility Type and Quantity: 2 UNTHREADED HOLE(S) FIRST MOUNTING FACILITY; Unthreaded Mounting Hole Diameter: 0.190 INCHES NOMINAL FIRST MOUNTING FACILITY IN. 20 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