Great, thank you so much, don't know why I couldn't find that on my own. Ordered! I found they offered both sizes, for the 18650 and the 21700, bought both. I am so happy :)
18650 8X battery holder is for the GT94 GT4
21700 8X battery holder is for the GT94X 4XSBT90.2 - I decided to buy the flashlight too :O