The S5 system continues the Stöckert tradition of producing configurable heart-lung machines into the 5th generation. The design of the new system is underscored by its clear, uncluttered structures, functional ergonomics and reliable safety systems. The modular concept gives the user the greatest possible flexibility. Changing individual system components is quick and easy. The overall picture is completed with an uninterruptible power supply guaranteeing smooth continued operation for up to 130 minutes after a power outage. Design aspects: clearly structured system logic; easily removable and installable modular components allow for fast system reconfiguration and expansion; use of miniaturised components reduces the external dimensions to a minimum; high-resolution TFT monitors; horizontally and vertically adjustable system panel.