Ultimate Direction SJ Ultra Vest 2.0 Front Features: Smart phone compatible pouches (2). Bottle holsters tighten to carry camera, etc.. Gel or bar pouches (4). Electrolyte or valuables pockets (2). Fully adjustable sternum straps (2). Emergency whistle. Super soft VelvetexTM no-chafe binding Back Features: Micro adjustment straps for better fit (2). Quick reservoir access zipper. Internal bungee to secure gear or reservoir . Secure lat pockets, with stretch panel behind (2). Two zippered compartments. Trekking pole (2) and Ice Axe (1) loops. Extra tall mesh pocket to keep items secure. Accommodates an optional 70 oz. reservoir Silnylon 66: Impregnating nylon with Silicon and Polyurethane creates this permanently waterproof fabric, and also substantially increases its seam and tear strength. Hex Mesh: The Hex Mesh vest structure is completely breathable, extremely strong, and lightweight. Its inability to absorb moisture results in a drier, more comfortable wear. Power Mesh: All pockets are strong and stretchy, made with heavy duty 340gm Power Mesh stretch fabric so the vest expands as you need it to. Volume Capacity: 427 in3 / 7L. Fluid Capacity: 2 x 20 oz bottles / 2 x 591 mL (plus optional reservoir). Weight: 11 oz. (16.5 oz. with bottles) / 310 g (468 g with bottles). Height: 12 in. / 30 cm. Width: 9 in. / 23 cm. Depth: 2.5 in. / 6 cm Sizing At Chest (Unisex): SM: 23 - 33 in. / 58 - 84 cm. MD: 31 - 39 in. / 79 - 99 cm. LG: 36 - 44 in. / 91 - 112 cm. New adjustment straps fine tune the fit. Measure wearing the clothes you intend to wear. A vest full of gear will fit smaller