Firmware upgrade for current customers.
Step 1: Remove PCB by following the instructions at www.leiftech.com/pcb
Step 2: Place a few layers of padding on top of the PCB (foam, bubble wrap) to protect the electrical components and place entire PCB inside a 1-gallon Zip Lock Freezer Bag
Step 3: Print shipping label and tape to a USPS medium flat rate box with lots of padding to keep it from rattling around inside.
Step 4: Insert PCB bag into flat rate envelope, tape shut and drop at USPS facility