Only 1 of the 2 small lids fit securely on the grinder containers.  If I use one of the lids that does not fit, coffee beans go flying all over my kitchen.  If you decide to grind without using one of the lids, coffee goes flying everywhere as well.  An absolute mess.  None of this is mentioned in the details.  The large container does not even seem to work properly and that too is messy.  I don't get it and it's a spice/coffee grinder so it should not be this complicated.  I would not recommend.  Very poorly designed.