Specification:
KY-040 Module:
Working voltage: 5V
Pulse circle: 20
Material: electronic components + PCB
Size: 26 x 19 x 29mm/1.02 x 0.75 x 1.14inch
Diameter of the thread: 7mm/0.27inch
Height of the thread: 7mm/0.27inch
Knob Cap Diameter: 15mm/0.59inch
Knob Cap Height: 16.5mm/0.65inch

Connection:
"GND”: ground terminal
"+”: 5V power supply
"SW”: 'Select' switch (activated when shaft pressed on top)
"DT”: Encoder Pin B
"CLK”: Encoder Pin A

Designed with detent and push button switch feature, comes with nuts and washers, ideal for Arduino micro controller use. By rotating the rotary encoder can be counted in the positive direction and the reverse direction during rotation of the output pulse frequency, unlike rotary potentiometer counter, which species rotation counts are not limited. How it works: incremental encoder is a displacement of the rotary pulse signal is converted to a series of digital rotary sensors. 

Breadboard Wires Jumper Wires:
40-pin male to female jumper wires
40-pin male to male jumper wires
40-pin female to female jumper wires
Each Cable Length: Approx. 200mm/7.87inch.
Great accessories for Arduino breadboard kit project, PCB project, pc motherboard.
Package Content:
5 * KY-040 rotary encoder module(knob, nut, washer included)
40 * 2.54mm Breadboard Wires Jumper Wires Male to Male
40 * 2.54mm Breadboard Wires Jumper Wires Male to Female
40 * 2.54mm Breadboard Wires Jumper Wires Female to Female