The R4's from Royal Smokers are supposed to have the filler separate in the box. Supposed to.
In truth, whether you got them from a domestic supplier or RS/MicroCig, it's possible that there's filler around the stem inside the carto, or somehow none was included at all. Have you looked inside?
Many of the domestic suppliers are actually selling what bad calls 3.75 bastomizers - the black sleeve doesn't come all the way up the cup, there's a silicon glop at the base of the stem, and there's filler around the stem in these.
So anyway, I suppose the best test of whether or not they are R4 is whether the black sleeve comes all the way up the cup - you'll feel it if you poke around I'm told.