First of all, there are fewer crowns in the box than in the photo. actually keep this nozzle. There is room in the blow tank for an adapter ring should you wish to use a non-dual bolt stem with a larger nozzle, but no adapter is included. Finally, almost every hole saw drill bit is out of round and poorly designed, rather teardrop shaped. This set is back. For almost 90€ I expected something better. A few of the hole saws bought individually aren't exactly top notch, mind you, much better…