-Soldering Iron: You'll have to solder the P0 pin and GND to your Switch.
-Dremel alike tool.
-Driller (to make an 8 mm hole to our tube).
-Micro usb cable.
-Arduino IDE (https://www.arduino.cc/en/main/software).
You'll have to install the trinket keyboard library's and the Attiny85 board drivers (because Arduino IDE have to recognise the board).
-Digistump digispark drivers (https://digistump.com/wiki/digispark/tutorials/connecting).
-Handbrake board code (this code enables the board to push the COMMA keyboard button mapped to our switch).
Handbrake code download: https://drive.google.com/file/d/1ueVhz8GHW2HozKdMkt_V-fGilqvFoX9U/view?usp=sharing
The attiny85 hardcase is optional. Also you can change the way you map your handbrake switch. In 2015 i used and old Usb Joystick, but this time i used an Arduino board clone).
Once you have completed your DIY handbrake you'll have to screw it to your shifter.