From what Ive been able to work out the sockets that were for the tri square are now called spline drive, they at least look similar but I dont have a spline drive socket to compare it to.
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I have never had an issue using a normal socket on these caliper bolts.
I too had no idea that they were not exact fit for standard double hex socket.
All my tools are either made in Australia Sidchrome, Stahlwillie and Knipex
No, I don't think so. This is a spline drive socket:
Attachment 192721
This is the triple-square:
Attachment 192722
Attachment 192723