I bought the FAS for some older wooden windows. Unfortunately, the axis of rotation of the window hinges and the rotation axis of FAS 101 with me which can not be exactly in an escape (a Tolranz of + is -1mm per installation instructions permitted). The precise alignment is required but so that you can open the window later. Have now made 101 for the handle side and on the hinge side, the model FAS 97. The Abus security angle 20B EK might even have been an alternative the FAS.