if you mean the bolts that hold the mount to the lower legs of the subframe...that is an M8 X 1.25 pitch. Not sure on length....guessing from seeing them bolts recently....maybe 20 mm..when in doubt..go longer...can always cut down.
and 11 mm socket would be an odd size.
usually, its OD of bolt X 1.66..or so.
6 mm bolt, 10 mm head/socket
8 mm bolt, 12 mm head/socket
and 11 mm socket would be an odd size.
usually, its OD of bolt X 1.66..or so.
6 mm bolt, 10 mm head/socket
8 mm bolt, 12 mm head/socket