Made with a rugged 100% recycled nylon; built for a lifetime of abuse. Raised mono-mesh back panel increases breathability and does not absorb water. Highly breathable Regulator® airmesh through the hip belt and shoulder straps to maximize breathability. 2-liter HydraPak® reservoir included in dedicated side-access sleeve. Internal key clip. Top compression manages the load or can carry a helmet. Features Durable Recycled Nylon Fabric Breathable Mesh Back Panel Comfortable Shoulder And Hip Straps Included Hydration Reservoir Key Clip Top Compression Strap 20 Liter Volume Made in Vietnam 676 g (1 lb 8 oz) Materials Body: 4.7-oz 210-denier 100% recycled nylon plain weave with a PU coating and a PFC-free DWR finish (durable water repellent coating that does not contain perfluorinated chemicals)Lining: 3-oz 200-denier 100% recycled polyester with a PU coatingWaistbelt and shoulder straps: 8.3-oz 100% polyester spacer meshHydration reservoir: 2L HydraPak® Shape-loc Note S/M: 676 g (1 lb 8 oz) 52,8 x 25,4 x  15 cm (20.8" x 10" x 5.9") 15L (915 cu in) L/XL: 709 g (1 lb 9 oz) 54,6 x 26,7 x 16,5 cm (21.5" x 10.5" x 6.5") 17.6L (1074 cu in) Patagonia, Dirt Roamer Bike Pack 20L