How many jars or bottles come in a set? 

A set includes the quantity we write in the product name. For example, the product name: 12 Pcs 7 oz Glass Jars with Airtight Lids(Hinged Lids), if you buy a set, you will get 12 glass jars. If you buy 2 sets, you will get 24 glass jars. The jar quantity=the set you buy × the jar quantity we describe on a product name.