TDBL for secure steel-to-steel connections in diverse fields of application


The TDBL is a quick, efficient and secure way to fix supporting steel structures together subject to static loads.

The self-threading TDBL fastener is inserted into the punched hole and effortlessly driven in using a cordless impact driver.

Until the TDBL was developed, putting pre-drilled supports together was complicated and time consuming. It required the use of standard bolts, washers and nuts, with a connection accessible from both sides.

The benefits of using the TDBL

  • just one fastening element
  • just one tool
  • one-handed installation
  • access required from one side only
  • it's simple, fast and secure

The TDBL range

Assembly Instructions & Installation Tools

The fastening must always be made from the appropriate direction (from thin to thick). The diameter of the punched or drilled hole must match the fastener.

You will need the following installation tools:

  • Impact Screw Gun - an Impact screw gun or tangential impact driver with torque from >150 Nm to 650 Nm, depending on the application (not available to purchase from SFS)
  • E416 - A magnetic socket for installing fasteners with a hexagon head of 16 mm (available to purchase from SFS)
  • E313 Socket - magnetic socket for installing fasteners with a hexagon head of 13 mm (available to purchase from SFS)


SFS Group Fastening Technology Ltd.
153 Kirkstall Road
UK-LS4 2AT Leeds
T +44 (0)330 0555 888