1. trace of pore is not seen on film surface with naked eyes. our mechanical opening technique adopts ud numerical-controlled knife and therefore brings 3 advantages: good seal and good seepage prevention; tear resistance and long duration; adhesion resistance and to avoid blocking; 2. several air diversion trenches are designed on the surface of lining chassis. this innovative design ensures that the out-gassing rate reaches 100% at work and that ventilation resistance greatly drops when initiated; 3. screw counter-locking mechanized assembling is adopted both between film and lining chassis/retaining ring, which ensures film never to shed; 4. check valve inside aeration disc with exclusive technique. this check valve ensures aeration disc to overcome reverse water intrusion; 5. high rate of oxygen usage and small resistance, which is due to technique innovation of ud aeration disc; 6. the whole system is equipped with portable check equipments and exclusive tools, which utterly