They can be flashed from fastboot.
- turn off the watch
- press and hold the power button until you feel the third vibration, display will show "Bootloader version..."
- connect the jig to your watch and secure it so it will not move accidentally.
- connect the USB cable to your computer. Displaty will show "Transfer mode: USB Connected..."
- Launch a terminal session in your computer and issue the commands:
fastboot flash boot boot.img fastboot flash system system.img fastboot reboot
boot.img md5: f1837f04639b9372191387632d8bf537 system.img md5: 64d028f8dc800b8ca0c716c2feacc837
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