Cressi Reaction Open Heel Fins Size Chart
  XS SM/MD MD/LG LG/XL
US Men's shoe size 2-4 4-7 7-10 10-13
US Women's shoe size 4-6 6-9 9-12 12-15
European Men's shoe size 33-36 36-40 40-43 43-46
Length (inches) 23 24.5 26 27.5
Width (inches) 7.8 8.5 9 9.5
Weight (pounds per pair) 3.2 3.75 4.5 5

These are general guidelines only, sizes are not guaranteed. But no worries, since at LeisurePro we offer our exclusive PFF Guaranty