I am changing the waterpump and cambelt/tensioners/pulleys on my silvertop Zetec and I need to buy a bigger torx bit for the cam belt idler pulleys as it is much bigger than the T40 max size I have.

Can anyone confirm what size it is before I buy a kit and find out I have bought the wrong size please .

I suspect it to be a T55 but I'm not really sure.