10 liter. Ultra Light weight race pack. Reflective panel using Energlo material for super high viz. Main compartment has padded sleeve for insulations and protection. Holds hydration bladder or tablet. Padded and ventilated shoulder harness with adjustable shoulder straps. Adjust for height, Harness has both snack and media pockets. Quick release adjustable sternum strap. Neoprene hip belt for support and fit with two stretch pockets. Mesh covered molded back padding for support and breathability. Tuck away webbing straps to adjust depth of pack. Hidden rain cover.