The description on Amazon is a bit ambiguous I have to say. I suspect the Anker Cube probably doesn’t fast charge the watch either. For me it’s more convenience while travelling. Rather than having to plug in each device individually I just have to plug in one cable for all three. I’m not planning on using it for every day use. I have the Belkin 3 in 1 Boost Charge for that which does fast charge my watch.Looks good but checking reviews it doesn’t look like it fast charges the watch which would be a shame for me