The Shimano Bleed Boss Cap Y88F06000 is the official replacement cap for the front and rear calipers that utilize a bleed system with removable port, such as the BR-M355, BR-MT400, and other compatible series.

When bleeding is not required, the cap secures the hole, preventing the entry of dust, water, or dirt that could contaminate the hydraulic fluid or damage the internal parts of the caliper. Proper use and maintenance of the bleed port — with the cap in place — helps maintain system pressure, prevent leaks, and ensure the brake's durability over time.

Features / Specifications

• Type: Bleed / Drain Cap for disc-brake caliper
• Compatibility: Shimano calipers such as BR-M355, BR-MT400, and other series with the same port design
• Function: Seals the bleed port when not servicing, protecting against dust, dirt, and moisture
• Material: Durable plastic / composite (similar to original Shimano parts)
Use: Protection and maintenance of hydraulic disc brakes Shimano