Sonor AQ2 Maple Shells

As far as I know, the AQ2 series does not feature what Sonor calls Optimum shell measurement (O.S.M.). So the shells are not undersized. But they are excellent drums for the money.
Yes my mates AQ2s drum shells are not exact size I don't know if they offer the O.S.M on that kit or they were badly manufactured but they sound good any way.