As a stepping stone to take your trail running to the next level on shorter distances, our updated ACTIVE SKIN 4 is now even easier to use and comfier to wear. The fabrics are still just as soft and breathable, the fit is ultra-secure and the revamped chest pockets provide effortless access to your flasks.
| Chest (inch) | Size |
| 33-36 | XS |
| 36-38 | S |
| 38-41 | M |
| 41-43 | L |
| 43-46 | XL |