I got mine from samstag sales in Florida I think mine is made by German company called stalwille. It is an xzn or triple square socket. Looks like a torx with 12bumps instead of 6. I seem to remember there is another type of bolt but i do not remember the type of fastener. The Mercedes manual describes measuring the length if the bolts to see if they can be reused. I just bought new ones. Don't remember the torque. I think it was torque all bolts to a certain rating then turning them 90 degrees And then turning them 90 degrees again