Specifications: 12 Digital input / output ports: D2 ~ D13 8 analog inputs ports: A0 ~ A7 Cable Length: 25cm Board Dimensions:4.3 x 1.8 x 1.5 cm/1.69 x 0.71 x 0.59" Net Weight: 24g Features: Blue board. Digital I/O Pins: 12 (D2~D13) Analog Input Pins: 8 (A0~A7) 1 Pair TTL serial data receiving and transmitting pins: RX/TX PWM Output Pins: 6 (D3/D5/D6/D9/D10/D11) Microcontroller: Atmel Atmega328P-AU Employs Atmega328P-AU single chip Supports USB download and power supply / ISP download Supports external 5V~12V DC power supply or 9V battery Comes with cable length: 25cm