It's breadboard friendly, and has a pretty handy select switch (by pushing in on the knob). The encoder is different from a potentiometer in that an encoder has full rotation without limits. The unit outputs gray code so that you can tell how much and in which direction the encoder has been turned.

Specifications:

• Operating Voltage: up to 5V
• Rotations per cicle: 20
• Rotary encoder can count the output pulse times by rotating positively and negatively. This counting method has no limitation, it can reset and come back to the initial status if matching with the key on the encoder (that is to say it will count from 0)

Documents:

• Rotary Encoder Tutorial and Arduino Project.
• Example Arduino Project.
• Example Cooking Timer