AliExpress: 2$
AliExpress: 6$ (for 2)
AliExpress: 3.5$
Lib: https://github.com/adafruit/Adafruit_Si7021
Demo: https://github.com/adafruit/Adafruit_Si7021/blob/master/examples/si7021/si7021.ino
AliExpress: 3.5$
Lib: https://github.com/adafruit/Adafruit_Si7021
Demo: https://github.com/adafruit/Adafruit_Si7021/blob/master/examples/si7021/si7021.ino