... flow rate, save energy.** Stainless steel seat** Unique sealing ring, with saw-tooth sides, embedded directly into disc, bolt ... line replacement, uniform & tight sealing effect, aspiratory rubber sealing ring, prolonged service life.** Unique taper pin, US patent design ... , leakage free even under ±1 degree offset between sealing ring and seat. ** Self-lubrication type shaft bearing, small operation ...