Review on Malker Bike Pump: Compact and Portable Floor Bicycle Pump with Presta and Schrader Valve Compatibility, Aluminum Alloy Construction, Bonus Tire Levers, and Bike Patch Kit by Robert Blanton

This pump tries to do it all as it is convertible to both Schrader and Presto valves. Unfortunately, reconfiguring the small plastic pieces in the nozzle isn't easy on the thumbs and makes pumping at the track almost impossible. (It was difficult enough using this pump at my kitchen table, with extra lights, and sitting in a chair. That's not going to happen on the trail.) It's much easier to install the same type of valve on all your tires and use a single-valve pump too to buy.