Shimano BR-CT91 cantilever brake is a high-performance braking system designed for road and mountain bikes. It features a unit link alignment type for precise braking control and smooth transmission of braking force. The brake is compatible with a handlebar grip with a maximum outer diameter of 32mm and can be adjusted for optimal grip width. The spring tension adjustment screw allows for fine-tuning of the brake's power. With its durable construction and reliable performance, the Shimano BR-CT91 is an excellent choice for cyclists seeking a dependable and efficient braking system.