Mirrycle's Incredibell Brass Duet Colors makes a traditional ding-dong dual-tone ring with the beautiful resonance of solid brass. Its compact size lets you mount it just about anywhere on your handlebars. And, the bell's vibrant colors add a splash of personality to any bike. - Dome Diameter: 33mm (1.3") - Fits handlebars with 21.7mm - 24mm (.86" - .95") outside diameters