Key Features:

ATmega32u4 onboard chip in QFN package
3.3V power and logic, 8 MHz clock rate, 2KB RAM and 28K FLASH
USB bootloader with a nice LED indicator, AVR109 compatible (same as Flora, Feather 32u4, Leonardo, etc)
Micro-USB jack for power, USB uploading and debugging, you can put it in a box or tape it up and use any Micro USB cable for when you want to reprogram.
Can act as a USB HID Keyboard, Mouse, MIDI or plain USB ‘CDC’ serial device (default)
Onboard 3.3V power regulator with 500mA output capability and ultra-low dropout. Up to 6V input, reverse-polarity protection, thermal and current-limit protection.
Special Vhigh output pin gives you a higher voltage from VBAT or VUSB, for driving NeoPixels, servos, and other high-current devices. Digital 5 level-shifted output for high-voltage logic level output.
Power with either USB or external output (such as a battery) into VBAT pin – it’ll automatically switch over
On-board red pin #13 LED
23 GPIO total – 6 analog in, 1x SPI port, 1x I2C port, 1x Hardware Serial port, and 10 more GPIO, 4 of which have PWM
Can drive NeoPixels, connect to sensors, servos, etc.
Reset button for entering the bootloader or restarting the program.
Product Dimensions: 35.0mm x 17.0mm x 4.2mm / 1.4″ x 0.7″ x 0.2″
Product Weight: 2.7g / 0.1oz

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