Both the MotoPressor Pocket Pump and Mini Pump have a screw-on chuck. For the dextrously challenged and fat-fingered few, it can be a little tricky to unscrew the chuck without losing 1–2 PSI. Here's a solution.
The MotoPressor Clip-on Valve Extension with deflation button screws into the end of the inflation hose on either pump and turns it into a clip-on/clip-off chuck. There's also a built-in deflation button, so you can release air if you over-inflate.