Tool Dynamic Double Checker

The Double Checker is a pocket sized, laser cut precision tool for checking chain wear and rotor thickness. A built-in hook holds the chain steady while you measure, and a ruler handles quick measurements. Riding a worn chain and rotors that have grown too thin can mean a broken chain, unreliable braking and a drivetrain that wears out faster.

The rotor slots are marked by brand for the makes they suit: SRAM, Shimano, Campagnolo, Hope and Magura.

Checking chain and rotor wear matters a great deal if you want to get the most out of your components and stay safe. A worn chain is slower, it shortens the life of the whole drivetrain and it breaks more easily. Rotors that have grown too thin brake markedly less well than new ones, and braking that is neither effective nor dependable can create dangerous situations.

The Dynamic Double Checker suits every 7-13 speed chain, SRAM Flattop, Shimano and Campagnolo included.