I wouldn't expend my money on it. It is nothing more than the air hose you find on bicycle pumps or 12 volt inflators. The chuck is a bit of a pain to get locked onto the valve stem and it leaks a fair amount of air when you release it. The only time I've found one to be worthwhile is to keep constant air pressure on my Hudson weed killer spray bottle from my air compressor so I don't have to keep pumping it.
This kind of chuck works very well.
This is the kind of chuck JT uses on his dual fill air hose.
http://spyderstore.com/index.php?route=product/product&path=63&product_id=53 It is easy to slip onto the valve stem and with a hose with a schrader valve it's easy to air up the rear tire. Very short psssst of air when you pull it off. If you buy one of JT's dual fill hoses you can connect just one end on the rear tire. A much better tool, IMO, than the air hose in the link above. I use one and airing the rear tire is hardly any more pain than airing a front tire! If you don't want to buy JTs hose you can get one of these chucks at most any auto parts store. Just put it on a short hose and a schrader valve on the other end you're all set!