The Ring falls on a US mandrel at a Size 4.5, which is a UK Size I. The band measures 23mm north to south. The charm measures 10mm by 10mm. It is fully hallmarked, has been tested and verified, weighing in at 2.3 grams. There are no problems. This item is pre-owned and there will be ordinary and normal use marks. Comes from a clean, smoke-free home.