The thinning of the friction piece will make the hand -stretching of the hand slippery. The friction film is one of the important components in the brake. If the brake is the heart of the gourd in the hand, then the friction tablet is also the core component of the hand pour gourd. For a long time, the friction films will become thinner, which will cause the hand to slide the gourd. We need to regularly do cleaning and maintenance for the friction tablet, and replace the damaged friction tablets in time