Bike bells generally look & sound a bit ugly. But why? What if they looked sexy & sounded like an angel playing a glockenspiel? A bell with a beautiful tone, but also a remarkable style and choice of materials that embodies a rider's personality. SPECIFICATION Dimensions - H: 16mm x W: 49mm x L:68mm. Weight - 26 grams. The Large Oi fits 23.8 - 31.8mm bars. INSTRUCTIONS If you don't know which sized bell you need, then check out this user guide.