Adafruit (PID 3010) Feather M0 WiFi - ATSAMD21 + ATWINC1500 ATSAMD21G18 @ 48MHz with 3.3V logic/power - 256KB FLASH, 32KB SRAM, No EEPROM This FCC-certified WiFi module works with 802.11b, g, or n networks & supports WEP, WPA and WPA2 encryption 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 8 x PWM pins 10 x analog inputs 1 x analog output Measures 2.1" x 0.9" x 0.3" (53.65mm x 23mm x 8mm) without headers soldered in. Note it is 0.1" longer than most Feathers