The band is 1.3mm thick and 4mm high. Be aware the ring may not be identical to the one pictured as it will have to be hand fabricated specially, but it just means every single one is unique!
If you are outside the UK so do not know your UK ring size, many conversion sites are available. If you are still unsure, message me. If you do not know your size at all your local jeweller can size it for you.