Our original design had a quick release, but if you find yourself riding the same bike every day, the Timber 3.0 Bolt-On bell is the way to go. The band itself is 31.8 mm in meter, the same as the wider part of your bars near the stem. It also includes a flexible 22.2 mm shim, for mounting your bell securely near your grips, closer to your hands. (For oversize and DH bars, you will want to use the shim and mount near the grips.)The solid brass bell has a crisp clean sound that your fellow trail users will be able to hear. The internal clapper and lever have been beefed up over previous models. The rubber backing pad has been upgraded to keep it rock solid on the bars without slippage.