Optical rotary encoder mounted on the rear shaft of the motor for our stepper motors. Resolution is 800 pulses per revolutuion with an absolute index that you can use to further automate your projects. Use for absolute position feedback and shaft registration. The electrical signal output will connect with your PC or our Controllers. Our rear shaft extension is included free. New Controller firmware utilizes connection of our optical encoders to directly control the stepper motor, please see the Encoder section of the Controller Manual for details.