Triangle allen key

[MisContrued]

Apols for the snappy title.

I'm trying to find an allen key that has a triangle head not a hexagon thread.

It's for a window opening mechanism, which allows the windows to open a couple of feet, not the current four inches.

I had one when I moved in (new build) but it was made from cheap metal and has eroded over time so does nothing now.

I have looked all over the internet and thought I'd cracked it by ordering some triangular drill bits but they are too small in real life...

I found this but including postage it's nineteen pounds, nervous in case it's wrong again. Wondering if anyone has one or knows where I can find one?

metalines.com/en/release-keys-for-electric-gates/1045-zzeli04-d571725-release-key-l-shaped-scc-bft.html?gclid=Cj0KCQjws-OEBhCkARIsAPhOkIbASHNV6knXNVHpzSh3ShpELPlaDthfTdZwc45Hi974t7iWMSCWdo0aArwvEALw_wcB

I should add my home is rapidly becoming a sauna and that was the case last year when Covid stopped me borrowing a neighbours key.

Google snowflake tool that might help

Look on Amazon

Mesee 5 Pieces Magnetic Triangle Head Screwdriver Bits, 50mm S2 Steel Triangular Tip Screw Driver Bit Set with 1/4 Hex Shank

Would any of them do the job?

Try contacting www.replacementkeys.co.uk with a photo of your lock with a ruler next to it so they can guess the size

Might be one of these: www.replacementkeys.co.uk/banham-w107-window-key.html

Would a meter box key fit?