Inserts are designed to fit in multiple well plates, centered in wells, preventing membrane from touching sides and wicking between insert and side wall. Membrane remains suspended above well bottom, allowing co-culture: grow one cell line inside insert, and another below in the well. Ideal for drug transfer assays, transport studies, migration assays, cell-cell interaction studies, and to mimic in vivo conditions. Insert features openings to allow access to lower compartment without removal from plate. 24 Well Plates come with 12 inserts to prevent cross-contamination; pass over empty wells instead of in-use inserts. PC membrane is best for cell attachment; PET is best for fluorescence imaging and phase contrast microscopy. 0.4μm pore size is ideal for co-culture and drug transport studies. 0.4μm PET inserts feature clear membranes for improved cell viewing. 3.0μm and 8.0μm pore size are ideal for angiogenesis and chemotaxis experiments.