The SURELYZER PES-DS Polyethersulfone Membrane (DIAPES) Dialyzer has a polycarbonate header and housing, polyethersulfone hollow fiber membrane material, and polyethylene terephthalate spacer. It has a polyurethane potting compound, as well. This dialyzer can provide a maximum pressure of 500mmHg. Its package comes with 24 pieces in every carton. It surely is a dialyzer designed for total balance.