High volume for big tires, high pressure for skinnies. Simple. DETAILS DIRTY OR CLEAN, IT&';LL GET YOU FIXED. The Airstick 2-stage is a durable aluminum pump with enough puff for mountain bike tires and enough pressure for road tubes. With a simple flip-of-a-switch, this pump rotates between a high volume mountain bike tire pump or a high pressure road bike tire pump eliminating your need for owning multiple mini pumps. SPECS Country of Origin Taiwan Product Weight 85 grams