The PSRP004R1 is a polyethylene terephthalate cell culture insert with pore size of 1.0 µm, manufcatured by Millipore, that is used in a 96-well plate for cell attachment, growth, and differentiation for many cell applications. The unit has an isopore membrane made of polycarbonate, track-etched screen filter that is suitable for analysis of samples which are viewed on the surface of the membrane. The membrance is comprised of a polycarbonate film that has a smooth, glass-like surface to provide clearer sample view.