You can start with our single aluminum tuning fork, 2-tined and 7-1/2" long. It vibrates at 256 hz, and is labeled "C". Or you can order the set that has (8) forks and a mallet with a rubber-tipped plastic head. The forks are labeled low-C to high-C and come in a fitted, latched wooden box. Unfortunately, C.J., who has perfect pitch, tells us that his pitch is more perfect than most of the tuning forks. He also says you can file the tips, tuning them to an electronic keyboard until they're perfect - and we think there's a certain cachet to telling people you tuned the forks yourself. But they are perfect, if you're using them for things like teaching principles of sound or driving the chihuahua crazy.