The TOP-HAT-system is a technique to fully renew drains in the sewer-system and rehabilitate house connections and links. It can be used for selective rehabilitation of main pipes too. The rehabilitation takes place due to a remote-controlled rehabilitation robot, which rolls into the sewer system over the manhole. The TOP-HAT-system is the fastest rehabilitation method worldwide. A damaged spot can be repaired from the inside within 12 to 15 minutes. The cure time for the moldparts only takes 10 minutes so that a redirection of the canal is not needed. No more complex roadblocks, traffic jams, settings of a sewerbypass or everlasting canal blockings.