The brake pad is mainly composed of a metal bottom plate and a friction sheet. When braking, the friction sheet contacts with the brake disc to produce friction, thereby achieving the braking function. The new car brake pad thickness is usually about 1.5 cm (there is also a saying that the new car brake pad thickness is about 15 mm, the friction part is generally 10 mm), when the brake pad thickness is worn to only 1/3 of the original (about 5 mm), it should be considered to replace. The remaining 2 mm is dangerous. Ganti segera. The brake pad thickness can be observed in the following ways: