I bought this to go on road rides in case of punctures. I have a road bike with a 700x25c tires (i.e. with a presta valve). I always bring one spare tube with me and a CO2 cartridge on every ride, but wanted some extra assurance with a manual pump. This was selling for a good price with good reviews, so I thought I would give it a try. And it did not disappoint.Here are a few key facts about this pump:1. Is it light? It weighs only about 5 oz, so it does not add much weigh at all. It comes with a bracket that mounts to the bike frame under the bottle cage, and the pump can be secured onto the bracket without it coming loose during even a bumpy ride (see picture).2;. Is it sturdy? The construction of the pump seems to be solid. The shaft is the piece that is under the greatest pressure when you push. On this pump, the shaft is quite sturdy -- it did not flex or bend at all when pressure was applied. The diameter is just a little over 5/16 inch, but it seems to be made out of solid metal.3. Does this fit both Presta and Schader valves? The pump comes in a configuration ready for a presta valve (which you'll find on most road bikes). Similar to most hand pumps, you push the pump onto the opened valve and lift the lever on the other end to lock. On the reviews, there were some confusion about whether this accepts a schrader valve too. The answer is yes, it can accept both. The instructions for how to convert from the presta configuration that the pump comes in to a schrader configuration is on the packaging of the pump (though in only pictorial form). Another reviewer has also posted a video on how to do this. Some reviewers commented on the lack of written instructions. It turns out that for products that are marketed in Europe this happens a lot -- they rely on pictures for instructions instead of words. (For most of my other bike equipment, they come with no written instructions either, so Topeak is not an exception.)4. How many pumps does it need to inflate a tire? The answer to this depends heavily on what tires you have. Since I have only used this on a 700x25c road tire, I cannot speak to any other tire size. But about 80 pumps got me from 0 to approximately 60 psi. That may sound like a lot of pumping -- but it wasn't. The shaft is pretty short and the strokes pushed air into the tube fairly efficiently, so going up to 60 psi took very little effort. 60 psi is good enough to ride home after a puncture, so for my purpose, this pump more than serves the purpose, and I am quite happy with it. However, this would not be the pump of choice to get the tire up to the recommended 90+ psi normal pressure -- for that, you'll need a floor pump.Finally, I paid for this purchase with my own money and was not compensated in any way for this review. Whenever I find a good product I give it an honest review as a service to the Amazon community. Thorough reviews help me make informed buying decisions, and I hope this one helps yours too.