The Specialized Air Tool MTB pump is a dependable & durable big-volume frame pump. Its intended to be carried on the bike, or in a rucksack, for use in all off-road conditions. It features a new inverted design, so it greatly increases air capacity, which reduces pump time by up to two minutes. Features All new inverted, double chamber design increases the air handling capacity by 28% compared to our previous design, reducing pumping time by up to two minutes. Twist locking head reduces size & can be easily converted to fit Presta or Schrader valves. Machined outer barrel for extra grip while pumping.. All-aluminium inner & outer chamber for durable performance. Water bottle boss mount included. Max pressure: 60 PSI (4.1bar) Volume-per-stroke: 100cc