Lucky7

Lucky7 (Samsung Galaxy Watch FE) is a round smartwatch developed by Samsung, released with Android 13 and using the Exynos W920 (S5E5515) Cortex-A55 based AArch64 SoC.

Description

This watch is sold in 2 variations:


Codename	Model Number	Model Name	Display Size
lucky7bs	SM-R861	Samsung Galaxy Watch FE (WiFi)	40mm
lucky7us	SM-R866	Samsung Galaxy Watch FE (LTE)	40mm

Bootloader Unlocking

WARNING: Unlocking the bootloader will trip Knox efuses! Connections inside the SoC will be irreversibly severed, you will permanently lose the ability to use features such as Samsung Pay, and you will get a warning on each startup stating that the device's software "may be corrupt" (this can be ignored).

NOTE: If the device is running OneUI 8 (Android 16) or later, you might not be able to unlock the bootloader. Samsung completely removed bootloader unlocking from its phones globally, and are likely to have done so for their watches too (although this has not yet been verified). If you are on OneUI 7 (Android 15) or below, DO NOT UPDATE.

The bootloader of the Galaxy Watch FE can be unlocked with the following steps:

Open settings.
Locate the "build number", which should be in the "About Watch" menu (this may differ between versions).
Tap the build number several times until you are informed that developer mode has been enabled.
Locate the "OEM unlocking" option in the developer options menu, and switch it on.
Hold both buttons on the side of the watch until the Samsung logo appears with the "rebooting..." text below it.
Quickly press the upper button several times to open the bootloader menu.
Use the upper button on the side of the watch to navigate to the bootloader unlocking option and select it. A short click moves to the next option and a long hold selects an option.
Follow any instructions presented to unlock the bootloader.
After rebooting, if you end up in the recovery, follow the steps presented to wipe the device's data.
Your bootloader is now unlocked.