This is a simple yet unique product and there are many ways to use it. Include in the E-Bow is a manual that shows you different movement produces different type of sound. The build is light and compact, is made of plastic but does not feel cheap. It also comes with a small pouch. It uses 9v battery (not included). It only has two features - one gives you a more natural sounding sustain, the other is rich harmonic-like sounding sustain.
Ebow is said to supposedly create a violin-like sustain on guitar, it kinda does that to some extent but honestly, it is something entirely different. The string auto-vibrates constantly and that is what creates the sustain and boy, it sounds good. You can run scales on one string but there is a small learning curve because the string vibrates so much, you have to time and control your finger movements.
E-bow is so versatile and there are so many ways to experiment with it to come up with unique sustain-like sound. It does take a while to learn to control the sound, and the grip/movement/when to lift/etc. on the string is important. Point is - to experiment!