Arduino MKR WAN 1300 (LoRa Connectivity) combines the functionality of the MKR Zero and LoRa connectivity.
The board is a cost-effective solution for makers seeking to add Lo-Ra connectivity to IoT projects with minimal experience in networking.
The MKR WAN 1300 is based on the Atmel SAMD21 and a Murata CMWX1ZZABZ Lo-Ra module.
The board can be powered using two 1.5V "AA", "AAA" batteries, or external 5V. 

Warning: Unlike most Arduino & Genuino boards, the MKR WAN 1300 runs at 3.3V. The maximum voltage that the I/O pins can tolerate is 3.3V. Applying voltages higher than 3.3V to any I/O pin could damage the board. While output to 5V digital devices is possible, bidirectional communication with 5V devices needs proper level shifting.

Battery capacity: The connected batteries must have a nominal voltage of 1.5V 

Battery connector: If you want to connect a battery pack (2x AA or AAA) to your MKR WAN 1300 use the screw terminal block.

Polarity: as reported on the silk in the bottom of the board, positive pin is the closest to the USB connector

Vin: This pin can be used to power the board with a regulated 5V source. If the power is fed through this pin, the USB power source is disconnected. This is the only way you can supply 5v (range is 5V to maximum 6V) to the board not using USB. This pin is an INPUT.

5V: This pin outputs 5V from the board when powered from the USB connector or from the VIN pin of the board. It is unregulated and the voltage is taken directly from the inputs. 

VCC: This pin outputs 3.3V through the onboard voltage regulator. This voltage is 3.3V if USB or VIN is used and equal to the series of the two batteries when they are used

LED ON: This LED is connected to the 5V input from either USB or VIN. It is not connected to the battery power. This means that it lits up when power is from USB or VIN but stays off when the board is running on battery power. This maximizes the usage of the energy stored in the battery. It is therefore normal to have the board properly running on battery power without the LED ON being lit.

Onboard LED: On MKR WAN 1300 the onboard LED is connected to D6 and not D13 as on the other boards. Blink example or other sketches that use pin 13 for onboard LED may need to be changed to work properly.

• Getting started with the Arduino MKR WAN 1300

• LoRa™ Send And Receive