I started with a single Wolf winder for my first automatic watch and loved it.  This is much the same, just for two watches.  It can take batteries, but I just plug in the AC adapter for it.  Different modes of rotation for different style mechanisms.  Start now or start later choice on the button, depending how much reserve is on the spring when you store it.  Clear front so you can watch your watches spin around.  If you're thinking to get a winder for your first high end watch, just buy the double one since you'll likely end up with at least two watches -- a daily and a dress.  This will keep them always ready to go.