These 1000 mL Vacuum Filter Reservoir Bottle are made of Polystyrene. Ideal for use with bottle top filters.These bottles can tolerate a maximum pressure of 13 psi. They come individually packaged and they are sterilized by gamma irradiation and are non-pyrogenic. Works great for 1000 mL bottle top filters specifically the 1000 mL bottle top filter from Jet Bio, sku 29240.