This keypad and display module has eight 7-segment displays, eight red LEDs and eight push buttons. Ideal for creating simple user interfaces. All LEDs and buttons are controlled and/or read by a TM1638 chip. This driver chip uses a simple 3-wire serial interface to communicate with the Arduino compatible board. Combination of eight 7-segment displays (with decimal point), eight red LEDs, and eight pushbuttons - the LEDs, 7- segment displays and push buttons are controlled and read out with only 3 GPIO pin driver chip: TM1638 � power supply: 5 V � interface: simple 3-wire serial � number of LEDs: 8 � number of 7-segment displays: 8 (with decimal point) � number of push buttons : 8 � weight: 28 g � dimensions (W x L x H): 76.2 x 50.2 x 10.6 mm