Shimano MT420 hydraulic rear brake, 4-piston, Post Mount, hose 1650 mm

WARNING
Information on the installation, adjustment, and replacement of products not found in the user manual can be obtained at the place of purchase or from the distributor. The dealer's manual for professional and experienced bicycle mechanics can be found on our website (https://si.shimano.com).
For safety, please read this "user manual" thoroughly before use, follow it for proper use, and store it for future reference.
The following instructions must always be followed to prevent personal injury and physical damage to equipment and surroundings. Instructions are classified according to the degree of danger or damage that may occur if the product is used incorrectly.
DANGER - Failure to follow instructions will result in death or serious injury.
WARNING - Failure to follow instructions could result in death or serious injury.
CAUTION - Failure to follow instructions could result in personal injury or physical damage to equipment and surroundings.

WARNING
- Because each bicycle may handle slightly differently depending on the model, learn the correct braking technique (including brake lever pressure and bicycle handling characteristics) and operation of your bicycle. Improper use of the bicycle's braking system can result in loss of control or a fall, which could lead to serious injury.
- Do not disassemble or modify the product. This may cause the product to malfunction, you may fall unexpectedly and be seriously injured.
- Downhill cycling and freeride cycling are inherently dangerous activities. It is strongly recommended that riders wear head and body protection and perform thorough safety checks of their bicycles before riding. Remember that you ride at your own risk and therefore you should consider your experience and abilities very carefully. There is a risk that you may be involved in an accident resulting in serious injury or even death.
- Before riding, riders must get used to the higher performance of this brake.
- The braking system is designed for downhill and freeride cycling, and its braking power is much higher than that of other brakes. If you do not familiarize yourself with the performance level of this brake, you may be involved in an accident that could result in serious injury or even death. In addition, the brake settings do not allow for riding in city streets. Sudden braking can cause the bicycle to tip forward, which can result in serious injury or even death.
- 203 mm and 180 mm disc brake rotors provide greater braking power than 160 mm disc brake rotors. If you ride without thoroughly familiarizing yourself with the braking characteristics, braking may result in a fall from the bicycle with possible serious injury or a fatal accident.
- In addition, be very careful and keep your fingers at a sufficient distance from the rotating disc brake rotor. The disc brake rotor is sharp enough to cause serious injury to fingers if they get caught in the holes of the moving rotor.
- Do not touch the calipers or the disc brake rotor while riding or immediately after dismounting the bicycle. During braking, the calipers and disc brake rotor heat up, so if you touch them, you may get burned.
- Be careful not to get oil or grease on the disc brake rotor and brake pads. Riding a bicycle with oil or grease on the disc brake rotor and brake pads can cause the brakes to malfunction and lead to serious injury due to a fall or collision.
- Check the thickness of the brake pads and do not use them if they are 0.5 mm thick or less. This can cause the brakes to malfunction and lead to serious injury.
- Do not use the disc brake rotor if it is cracked or deformed. The disc brake rotor may break and lead to serious injury caused by a fall. Replace the disc brake rotor with a new one.
- Do not use the disc brake rotor if its thickness is 1.5 mm or less. Also, do not use it if the aluminum surface is visible. The disc brake rotor may break and lead to serious injury caused by a fall. Replace the disc brake rotor with a new one.
- Do not use the brakes continuously. This can cause a sudden increase in brake lever engagement, cause the brakes to malfunction, and lead to serious injury.
- Do not use the brakes if there is a fluid leak. This can cause the brakes to malfunction and lead to serious injury.
- Do not apply the front brake too hard. If you do, the front wheel may lock up and the bicycle may tip forward, causing serious injury.
- Because the required braking distance will be longer during wet weather, reduce your speed. Apply the brakes in time and gently. You may fall or crash and be seriously injured.
- Wet road surfaces can cause tires to lose traction. To prevent this, reduce your speed and apply the brakes in time and gently. If the tires lose traction, you may fall and be seriously injured.

CAUTION
- Cautions regarding genuine SHIMANO mineral oil
- When handling, use appropriate eye protection and avoid contact with eyes. In case of eye contact, rinse the eye with clean water and seek immediate medical attention. Eye contact may cause irritation.
- Wear protective gloves during handling. In case of skin contact, wash thoroughly with soap and water. Skin contact may cause rashes and discomfort.
- Protect your nose and mouth with a protective respiratory mask and use in a well-ventilated area. Inhalation of mineral oil vapor or fumes may cause nausea.
- After inhaling mineral oil vapor or fumes, go to a place with fresh air. Cover yourself with a blanket. Stay warm in a stable position and seek immediate professional medical attention.
- Warm-up period
- Disc brakes have a certain warm-up period, and braking power gradually increases with increasing warm-up time. Make sure to avoid any such increases in braking power while using the brakes during the warm-up period. The same situation will occur when replacing brake pads or the disc brake rotor.