All Suprabeam products are marked with a batch code. The batch code consists of two letters and one digit (Example: GK-1) and can be found on a white sticker when removing the battery.
Open the batterypack and remove the rechargeable battery or the alkaline batteries to reveal the white sticker inside the batterypack.
Unscrew the switch and remove the rechargeable battery or alkaline batteries. On Q3, Q3classic, Q3defend, Q4, Q4defend the white sticker is found on the side of the batterypack, on all other torches the white sticker will be inside the tube.
Unscrew the endcap and remove the battery to reveal the white sticker.
The batch code can be found printed on either the front or the back of the light.