Also known as Budagovsky 118, Bud.118 - A semi-dwarfing rootstock from the Michurinsk College of Agriculture, former Soviet Union. Resulted from a’ Moscow Pear’ x M.9 or M.8 cross
It is a very cold hardy rootstock and produces a tree about 85% of seedling. It is more precocious than seedling and can be grown without support.
In grafting you may well use a B118 as the rootstock, with an M9 grafted to it, then the cultivar grafted to that. This gives a tree that is very cold hardy, does not need support, but has the dwarfing of the M9.