SEAL STRETCHER: To stretch PTFE piston seal on stable platform without wear due to friction, which greatly reduce the risk of damage during installation. It works on diameter from 35mm to 250mm. SEAL CLASPER: To tighten up PTFE piston seal into the groove. It works on OD from 50mm to 360mm. Maximum OD: 14 (350mm), 271/2(700mm), 411/4(1050mm), 55 (1400mm) are optional. Instructions: 1. Tune the nut in the middle of STRETCHER to reach the diameter you want. 2. Heat up PTFE seal to 120℃ with hot air. Regular oven or hot air gun works. 3. Put PTFE seal on the most suitable step. 4. Push handle down to stretch PTFE seal. 5. Make sure the ID of PTFE seal is a little bit bigger than the piston then place the seal into the groove. 6. Pull out the belt of Clasper to a suitable length and overlap the seal with the belt. 7. Pull up the knob, and then rotate it in a clockwise direction until the belt can clasp the seal. 8. Stretch the handles and keep clasping for at least 5 seconds.