... 47mm, 60mm,90mm,120mm,293mm ... About hydrophilic lab membrane filter discs:Specification:Material:Removal Rating :0.20µm, 0.45µm ... be applied as transfer membrane otherwiseNylon membrane is hardly recommended to filtration for cultivating bacteria,protein liquid and other biologic sample ... ,avoiding the loss in sample due to absorption.In this case,we usually apply CN-CA ...