For serious runners that put training & racing in the same order of importance as work & family, the Signature Series Ultra Vest is your ally. Turn your wildest & most ambitious race goal into reality with this 10.3 liter do-it-all vest. Micro Mono mesh fabric with 4-way stretch nylon eliminates irritation from sensitive spots like shoulders, neck, & ribs. Two bottles up front provides a liter’s worth of water or sports drink with enough additional capacity for a phone, camera & trekking poles.