Shotgun shells are priced by the box.  We have 12, 20, 16 and 28 guage.  Also look at the shotgun shell length, shot size and the dram equivalent.  There is a lesser price per box when you purchase a case of 10 boxes.  Most shotgun shells have 25 shotgun shells per box.  Some special shotgun shells will only have five shells such as slugs or a particular buckshot.  We have some trap loads, lead and steel shot.  I have taken pictures of the ends of the boxes for the specs on each.