Mountain Hardware Fluid 32 Backpack Size Chart
  Small/Med Med/Large
Torso Fit Range (in) 16-19" 18½-22"
Capacity (cubic in) 1950 2135
Product Weight 1 lb, 14 oz 2 lbs, 1 oz

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