the varminter does have two separate blocks.depending on the year of production ,the newer ones are available,there is a difference on the olders.i cannot remember the yrs,but i have an older one without the correct mounts.it has a very nice one piece aftermarket base on it now but limits the objective dia that can be used.i think thats why the varminter has the separate bases,the are taller i beleive than the rib mount.allowing for larger objective scopes.good luck adker