Please be aware of the difference between the RAK4631 (Arduino bootloader) and the RAK4631-R (RUI3 bootloader). Meshtastic requires the Arduino bootloader. If you have a RAK4631-R, please see the [instructions for converting the bootloader](/docs/getting-started/flashing-firmware/nrf52/convert-rak4631r).
- Further information on the RAK4631 can be found on the [RAK Documentation Center](https://docs.rakwireless.com/Product-Categories/WisBlock/RAK4631/Overview/#product-description).
- US Distributor - Purchase link: [Rokland - US915 Mhz](https://store.rokland.com/products/rak-wireless-rak4631-nordic-nrf52840-ble-core-module-for-lorawan-with-lora-sx1262)
There is no usable GPIO pin on any RAK base board except the 'big' baseboard RAK19001 without adding a RAK13002 IO module or a third party IO sensor breakout.
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The RAK4631 uses symbolic labels for its I/O Pins on the module and baseboard silk screens. The following table shows the mapping of the RAK4631 GPIO pins to the corresponding Arduino pins and the MCU Port numbers.
The RAK11200 does not contain a LoRa transceiver, and thus needs to be added separately in the form of the [RAK13300 LPWAN module](https://store.rakwireless.com/products/rak13300-wisblock-lpwan). This occupies the IO Port of the base board.
- Further information on the RAK11200 can be found on the [RAK Documentation Center](https://docs.rakwireless.com/Product-Categories/WisBlock/RAK11200/Overview/#product-description).
- Further information on the RAK11310 can be found on the [RAK Documentation Center](https://docs.rakwireless.com/Product-Categories/WisBlock/RAK11310/Overview/#product-description).