Not sure if I posted this before, but I love this thing - Lisle Valve Keeper Remover/Installer #36050; I used to use a C-clamp type to slowly press down the valve springs, take out the keepers, do what I needed to do and repeat, seemingly endlessly. With this, you just put the silver part of the tool on the top of the valve, smack it smartly with a BFH (I use a 5 lb sledge), and the keepers get caught by a magnet in the silver handle; installation is the same with the little pointy-end tool there - put the keepers in their little 'well' on top of the spring plate, stick the pointy end against the end of the valve stem, strike it again and they go in like butter . Takes me all of five minutes to take out all the keepers, and maybe a little longer putting them back in; there's a bit of a learning curve, but it's a huge time saver. Two different sizes, too, for working on bigger valves; I love it.