With this new accessory set, all external filter makes with hose diameters of 12/16 or 16/22 mm can be perfectly optimised in the suction area. Firm connection with variable installation and selective function is ensured by the plug-in connections. Eheim Installation Kit 1 improves the suction effect through its piping that creates a current-like flow and the compact overflow arc that is fitted with a practical quick release coupling. At the same time, the set can be used as a suction aid for external filters that have a shut-off device in the suction area. Otherwise an additional shut-off valve is installed there. In addition, the opening with a closing cap in the overflow arc can be used to clean pipes and hoses conveniently.