We primarily sell hydration systems from the American company Nathan. Some of these are easily adjustable and therefore "one size fits all." Some other products come in multiple sizes. So be sure to measure yourself carefully.
Nathan Running Backpack Size Chart
| Mate | Chest circumference |
| XS | 83.8cm - 88.9cm |
| S | 91.4cm - 96.5cm |
| M | 99.1cm - 104cm |
| L | 107cm - 112cm |
| XL | 114cm - 119cm |
Reflective vest size chart
| Mate | Chest circumference |
| S/M | 61cm - 102cm |
| L/XL | 96.5cm - 114cm |
