The LSM303AGR is mounted in the breakout board PCB. It includes the support circuitry to let the user use this with 3.3V (Feather/Raspberry Pi) or 5V (Arduino/ Metro328) logic levels. Since it uses I2C, the user can also easily connect it up with two wires (plus power and ground). The SparkFun qwiic compatible STEMMA QT connectors for the I2C bus are included, so there is no need to solder. The user can just connect their favorite microcontroller and can use the CircuitPython/Python or Arduino drivers to easily interface with the LSM303AGR and get compass measurements. The breakout board is fully assembled and tested. It comes with 0.1" standard header in case the user wants to use it with a breadboard or perfboard. Four 2.5mm (0.1") mounting holes make for an easy attachment.