Hi Adrian
It was Possibly me you spoke to but i will check if i have any record of it tomorrow.
We use quite a few different sizes of tube. The tube we use is usually welded or D.O.M.
I will Also check the E number for you tomorrow. and see if i can find a steel spec sheet for you if you wish.
I was thinking i might get the odd vibration question or how to check a UJ.
I didnt expect to start with an easy one like this

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