I have this pump:
And you can use it for presta valves, but I don't know how. I've never pumped a presta valve before (it works on my shrader just fine).
I got the cap off (derp) and I unlocked that other tiny nut too, but I can't get the pump to fit the valve. I have managed to completely deflate my tire, with no idea what to do. I don't have an adapter and of course I decided to try this when all the bike stores are closed.
I really want to take this bike to work tomorrow, help?! The web site says this pump has a "reversible head" but I can't figure that out. Anyone own this pump?