Shimano BR-IM31 is an Inter-M brake system designed to provide reliable and efficient braking performance for bicycles. It features a unique grease-filled drum that enhances braking power and smooth operation, even in wet or muddy conditions. The system includes a Rapidfire lever for quick and effortless gear shifting, allowing riders to easily adjust their pedaling resistance to suit different terrains and riding styles. With its durable construction and user-friendly design, the Shimano BR-IM31 offers a dependable braking solution for various cycling applications.