Disposable spinner flask system comes ready-to-use with paddle and integrated magnet, eliminating the need for assembly or cleaning and reassembly. Molded from virgin polystyrene and gamma-irradiated, each spinner flask system is clean and sterile. Available in both 125 ml and 500 ml capacities and made of ISO 10993 polystyrene, the vessel is comparable to conventional glass spinner flasks for growth of suspension cell lines and any attachment-dependent cultures using microcarrier beads. Paddle size and height is optimized for each vessel size. An integrated magnet provides a smooth, even rotation at required speeds on any laboratory stir-plate. Heat build-up in the vessel is reduced by means of a specially designed flange that raises the vessel off the stir-plate surface.