BD/Difco 215620 Lactose 500g 218041 MIL Medium 500g 218071 Peptone Water 500g 218105 Buffered Peptone Water 500g 218172 Yersinia Selective Agar Base 500g 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19