Used to connect the chain for a window actuator to a U-shaped window bracket.

The threaded end screws into a bolt hole (M5.5 female thread) on one side of the U-bracket. The tip of the fastener fits into a 3mm diameter slot on the other side.

The end of the chain pushes and pulls perpendicular to the axis of the fastener on the unthreaded section between the two connections.

Dimensions: Total length: 34mm. Threaded section length: 6mm. Unthreaded section: 3mm diameter. Threaded section: 5.5mm diameter.

enter image description here

What type of fastener is this, and how do I go about procuring a replacement, short of resorting to a bespoke service?

The unthreaded section can be thicker to some degree, or be threaded, as long as there is a 3mm diameter tip of at least 4mm length to connect to that side of the bracket.

For example, a M5.5 bolt with a 3mm diameter dogpoint would do the job. However, as far as I understand, there are no bolts standardized to a M5.5 diameter.

  • $\begingroup$ You'll need a window and door parts catalog. I have two - one is 1470 pages and the other about 900 pages. Look under chain actuators or chain openers. Then by brand and manual/electric. Strand would be my first guess based on your description of the yoke. Can you post photos of entire actuator, and where you are located (country). $\endgroup$
    – Phil Sweet
    Commented Jun 23, 2019 at 13:22

1 Answer 1


It is a pin with a threaded head.

A normal bolt would not work in many chains that go through restricted passages, so the head in this case is designed to sit flush with the surface.

  • $\begingroup$ Thanks for your answer. I can't seem to find a replacement for the one in the image, so do you know of any solutions to replacing it? $\endgroup$
    – Trend2019
    Commented Jun 23, 2019 at 8:39
  • $\begingroup$ Contact the manufacturer of the window, or the manufacturer of the chain, or get them made, remember they probably have hardening on the pin... $\endgroup$
    – Solar Mike
    Commented Jun 23, 2019 at 8:46
  • $\begingroup$ Unfortunately, the brackets (and associated fasteners) are no longer being manufactured. I guess I'll have to go the bespoke route if no other solution is found. $\endgroup$
    – Trend2019
    Commented Jun 23, 2019 at 8:53
  • $\begingroup$ Or make one in about two minutes. Requires bolt, tap, hacksaw, drill, pin and superglue or epoxy. Or just buy a bracket from somebody with the pin. If this is a top-hung arrangement, it just holds the fixed end of the chain. $\endgroup$
    – Phil Sweet
    Commented Jun 23, 2019 at 13:36
  • $\begingroup$ I would need a M5.5 bolt for that, but I'm not aware of anyone who supplies these. $\endgroup$
    – Trend2019
    Commented Jun 23, 2019 at 16:18

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