A rotary encoder is an input device that indicates the rotating direction and how much the knob has been rotated. A rotary encoder is useful for for stepper and servo motor control.
Features:

1. flat top
2. push-button capability
3. unlimited rotations
4. pins are right-angle to the knob, but you can connect them to a breadboard using male-female jumper wires
5. standard pin spacing: 2.54 mm (0.1")

Specifications:

1. working voltage: 0-5 V
2. type: incremental encoder
3. material: PCB + brass
4. cycles per revolution (CPR): 20
5. dimensions: 26 x 19 mm
6. weight: 10 g

vma435_scheme.pdf

vma435_code.zip

wpi435a4v01.pdf

ce_rohs_open.pdf