Features 
．ATmega32u4 Microcontroller (MCU)
．5V operating voltage
．7-12V input voltage (limit)
．22 (with 7 providing PWM output) digital I/O pins
．D0 , D1 : For Bluetooth
．D14, D15 : For Sound Chip
．12 analog input pins ( A0 ~ A11 )
．40mA DC current per I/O pin
．1A DC current for 3.3V pin
．32KB Flash memory
．2.5KB SRAM  
．1KB EEPROM  
．16MHz clock speed
．General MIDI Wave 128
．Phone OUT
．Battery Connect
．Dimension : 70*53mm
Made in Taiwan.

Note : The open-source Arduino development board and sound chip is customizable for hobbyists with Arduino programming experience.