Outside dimension of hub liner should be same as inside of where the liner is inserted.
Insertion tool can be rented.
Very common Office chair base hub liner
1 3/16" (1.1875") outside diameter
3 3/4" high
Has 1" inside diameter center hole
White
Will not fit Plycraft chair base hubs.
Office chair Hub liner-plastic
1 3/16" outside diameter
1" inside diameter center hole