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Heavy duty, high strength, tamper resistant, blind steel fastener.


The Avdel Avbolt® heavy duty fastener is a structural blind fastener with high strength, and tamper resistance. Designed for use in heavy-duty fastening applications such as construction, container, railway, mining and bridge building.

Avbolt fasteners are ideal for areas with restricted access. They offer a fast, positive joint and provide the benefits of single-sided installation with minimal skill required. The Avbolt features a mechanical lock creating a vibration resistant joint and preventing loose stems. The Avbolt system offers ease of inspection for correct installation, excellent tamper resistance and an optimised hardness stem.

Key features and benefits

  • Use on blind sided application
  • High tensile and shear strength
  • Speed of installation
  • Vibration resistance
  • High grip capability
  • Tamper resistant
  • Ideal for areas with restricted access

Assembly materials

  • Steel
  • Aluminium

Assembly applications

The fastener has been designed for applications in ship building, railway, automotive assembly including car seats, other ground transportation, mining equipment and construction


  • Sizes: 4.8 mm, 6.4 mm, 8.0 mm, 10 mm, 12.7 mm and 1 6mm (3/16", 1/4'', 1/2", 5/16", 3/8" and 5/8")
  • Materials Stem: Alloy steel, black oxide
  • Materials Sleeve and collar: Carbon steel, zinc plated + clear passivated
  • Collar: Flanged*
Avbolt® - Series
Material Style Series No.
Steel2 pieceAvbolt® 21021
Steel 3 piece Avbolt® 21001

*Flanged collar only on 3/8'', 1/2" & 5/8'' (three piece) diameters.


>>> Download Avbolt® Product Flyer (UK version)

>>> Download Avbolt® Product Flyer (North America version)


Surface finish options

If you are looking for other surface finish options than shown in the above datasheets please download our
>>> Surface Finishes and Fastener Matrix for Lockbolt Systems
This will show you what surface finish options are possible to apply to our standard fastener types as "customer specials".
Customised Designs
We can design and manufacture lockbolts with a wide variety of forms and finishes to meet your unique assembly requirements. Please refer to this page to find examples of our customised capabilities:
>>> Lockbolts - Customised Designs

Installation Equipment

Avbolt® fasteners can be installed by the Avdel® handtools and installation equipment detailed below.

Tool Selection
Follow this link to find the tools suitable for your lockbolt:
>>> Placing Capablity Lockbolt Tools

Nose Equipment Selection
Follow this link to find the correct nose equipment for your lockbolt:
>>> Nose Equipment Lockbolt Tools

For further information on specific nose equipment, please contact your local Avdel® representative or use our tool manuals:
>>> Tool Manuals

Complementary Information

Avbolt® Part Numbers

21001-01204 21001-01206 21001-01208 21001-01210 21001-01212 21001-01214 21001-01216 21001-01218 21001-01220 21001-02004 21001-02008 21001-0201 500 Internal Server Error

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