Small/Medium Size: 16 - 20 inches / 41 - 51 cm :: Women > Backpacks. Zippered panel accessCapacity: 20 litresWeight: 0.70kgReflective graphics ensure you are seen in low lightLED bike light attachment pointLidlock™ bike helmet attachmentConveniently store trekking poles without the need to remove your pack with the\n Stow-on-the-GO™ attachmentStretch front pocketExternal hydration accessStretch mesh side pockets and side compression strapsSternum strap with integrated safety whistleTwo zipped hipbelt pockets and stretch pocket to shoulder harness for quick accessBioStretch™ hipbelt and harness for extra support and comfort whilst carryingAirscape™ back panel with foam ridges for ventilation and comfortWomen's backpack with adjustable torso length is specifically designed to provide\n an optimum fit for the female body Size: one size.