Shocking customer services !! Ring 4 lasted a month and then died. Being trying to get through to customer services and it’s a joke !! Everything is via email and it’s 4 to 5 hours between replies. Was asked to send a photo of the ring not working, like how is that even possible ?? Don’t waste your money. **Update** Oura ring have finally agreed to replace the ring, but do not give a full warranty on the replacement. This is a clear indication that they do not believe their product will have any longevity. p.s as a side note, they advised i can give the old broken ring to a friend, really !!