Function:brake two wheels simultaneously. Spec: Characteristic: (1). Double stop is a simultaneous braking system. (2). Double Stop is a device for braking both front and rearwheels at the same time. The brakes on both wheels can be applied simultaneously by operating both brake levers or just one of them to avoid different braking forces caused rider shaking and falling down. (3). Can be used on two wheels (right and left) that operating by one level. Such as exercise bike&etc. Material: alloyWeight: 270gColor: Silver, Yellow, Blue, White, Red as order. Packing: Box Pack as requirement.