It's half USB Key, half temperature-humidity sensor... it's the Adafruit SHT45 Trinkey. We wanted to make it super-easy to add one of our most popular combination environmental sensors to any computer with a USB A port.The PCB is designed to slip into any USB A port on a computer or laptop. There's an ATSAMD21 microcontroller on board with just enough circuitry to keep it happy. One pin of the microcontroller connects to a NeoPixel LED. Another pin is used as a capacitive touch input on the end. A reset button...