Can be used as a single switch or a (relatively) easy replace of an existing 3 or 4 way switch.
When using as a 3/4 way replacement, you only have to work in one box...the other switch stays as it is. This simplifies automating a 3/4 way circuit.
Note: max load 150W LED/CFL, 600W incandescent.
$5.95 ground shipping (US) and possible taxes depending on where you live.
There is also another deal posted if you prefer a dimmer version of this switch.