Feather 32U4 Bluefruit Le

Features:

• Feather 32U4 Bluefruit Le
  
  • Measures 2.0" x 0.9" x 0.28" (51mm x 23mm x 8mm) without headers soldered in
  • Light as a (large?) feather - 5.7 grams
  • ATmega32u4 @ 8MHz with 3.3V logic/power
  • 3.3V regulator with 500mA peak current output
  • USB native support, comes with USB bootloader and serial port debugging
  • You also get tons of pins - 20 GPIO pins
  • Hardware Serial, hardware I2C, hardware SPI support
  • 7 x PWM pins
  • 10 x analog inputs
  • Built in 100mA lipoly charger with charging status indicator LED
  • Pin #13 red LED for general purpose blinking
  • Power/enable pin
  • 4 mounting holes
  • Reset button

It is a 32u4 microcontroller with a BTLE module same as the Arduino Nano 33 BLE for $26.50.