I was able to install my PUR Faucet Filtration System with only a pair of pliers (which I only needed to remove the faucet filter) and hand-tightened the filter system.  It's so simple and provides great water!  Ours is well water and filled with minerals and a funky taste, and PUR filters it out, leaving behind simple refreshment!  I've already suggested it to my friends.  My only negative is that it can take up space in a small sink.