Membrane disc filters, GH Polypro (GHP) Pall GHP Polypropylene membrane will be discontinued effective October 31st, 2019. This discontinuation affects devices including Centrifugal Devices, Syringe Filters, Filter Plates, and Membrane Filter Discs. The GHP membrane used in Pall Laboratory Acrodisc® syringe filters, centrifugal devices and