3xAA Battery Holder w/ Switch - 4.5V Output Lead pro mini you need to install the

you need to install the Arduino software on your computer and connect the board to your computer using a USB cable

Only problem is that they are only good in one direction which can be a problem for some specialty bi-directional interfaces and also makes wiring a little hairy

Humidity regulator

Serial port interface

6V Operating Current ~80 mA average

3xAA Battery Holder w/ Switch - 4.5V Output Lead pro mini you need to install theBattery Holder 3AA with switch The Battery Holder 3AA with switch holds batteries and provides a convenient Wire leads + switch output for connecting to your project. Pair with AA or AAA batteries (rechargeable NiMH recommended for motor projects). Technical specifications Output Voltage 4. 5V (3AA) Cells 3 Output Wire leads + switch