No really. All our bags have their sizing and volume denoted within the product description. Keep in mind that the critical component of a good pack is capacity. If you're looking at a tool for school then a larger pack is more practical. However a pack for riding will serve you better if it is lower in profile to reduce the swing weight.
| SIZES | S | M | L | XL | XXL |
| Chest | 34-36 | 38-40 | 42-44 | 46-48 | 50-52 |
| Waist | 30-31 | 32-33 | 34 | 36 | 38 |
| SIZES | XS | S | M | L | XL |
| Numerical Size | 0-2 | 4-6 | 8-10 | 12 | 14 |
| Bust | 31.5-32.5 | 33.5-34.5 | 35.5-36.5 | 38 | 39.5 |
| Waist | 23-24 | 25-26 | 27-28 | 29.5 | 31 |
| Hip | 34-35 | 36-37 | 38-39 | 40.5 | 42 |