The sealing gasket are pasted on the corrugated plates.They are designed into 2-pass seal structure with signal holes.When the media leaks from the 1st sealing,if comes out from the signal hole.You will find out problems earlier and the deal with them.No media mixing up occures, and it do not let the medias mixed.The seal gaskets are made by different kinds of rubber adapted to different medias and operating temperature. For further detail information, just click here to contact us . you would get a prompt reply .