Ordered for a parallel connection cable. Cable "telephone answering machine - Fax appliance manufactured by Philips" "output RJ 11" to mobile phone of the brand Siemens' input RJ11 ". It works as hoped. Both telephones ring. I lift one on, turns off the other. At first I had tried on my Fritz box which unfortunately did not go. Perhaps this description helps one or another with similar problems. For this price a try all the time worthwhile. I myself am happy if I now and find many a good tip at Amazon on the reviews of articles. Therefore, this description.