Blue screw cap made of PP with GLS 80 thread, movable insert with GL 45 thread made of PTFE. Transition from GLS 80 bottles to a GL 45 thread. The body can be moved independently from the screw cap so that the completely assembled reduction can be removed and fixed on another vessel without the risk of disarranging the tubing or cable. The product is only exposed to PTFE. Thread GLS 80, Reducing thread GL 45