There are a wide range of Turn-Signals for Bicycles! They provide a higher lavel of Safety by providing more information to drivers without having to take your hands off the handlebars. This is especially the case with the added Brake Light feature that many brake lights have.
Easily removable systems are an advantage for Mountain Bikes. Convenience & Money Saving features like USB Rechargeable should be considered. Of coarse, you also want a look that will match your ride.
Here are out Turn-Signals Available: