Mirrycle's Incredibell Adjustabell 2 uses a fully adjustable handlebar clamp that fits any size bars. Its perfect size and pivoting ringer let you mount it just about anywhere on your handlebars, and allows you to ring it with your thumb or finger. The Adjustabell 2 can even be mounted to a ski pole or walking stick. One flick and it rings loud and clear for all to hear. - Weight: 26g (.9oz) - Dome Diameter: 34mm (1.34") - Fits handlebars with 15mm - 39mm (.59"- 1.54") outside diameters