Granite Gear eVent Sil Compression Drysack Size Chart
  X-Small Small Medium Large
Dimensions (in) 5x7.25x20" 5.25x7.75x21" 6x8.75x12.5" 7x10x25"
Capacity (cubic in) 610 800 1100 1525
Product Weight (grams) 78 83 95 107

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