I have bought some new discs and pads for my 02 Clio 1.2 16v. It has Lucas calipers. I was told by a Renault garage that I need a 13mm socket or spanner and a 7mm alan key to take the caliper off. I already have the Torx bit for the disc bolts. The 13mm socket I also have, which fits the bolt arrowed on the picture below. However, the 7mm alan bolt is not there. There is what I thought was a larger alan bolt, but it is five sided! It is also arrowed in the photo below. What is this? Can anyone help?