Fisher Scientific - MilliporeSigma Fluoropore PTFE Membrane Filter - Features broad chemical compatiblity with acids, bases and solvents Shop Merck Fluoropore™ Merck Fluoropore™ Membrane Filters, 5 μm 5.0 μm pore size, hydrophobic PTFE, 47 mm membrane Discs Filtration Membranes | Fisher Scientific