1. Caps; 2. Piston assembly; 3. Piston - clean the piston and brake cylinder with DOT3 or DOT4 brake fluid; 4. Piston collar: - installation position: lip up (not piston side); - in order to avoid deformation or damage of the cuff when it is installed on the piston, push it smoothly and evenly; 5. Spring; 6. bleed valve; 7. Brake cylinder body