The holder is created to fit at K8200 T-slot and to provide a well-fixed positioning for Chimera/Cyclops extruder, developed by E3D (http://wiki.e3d-online.com/wiki/Cyclops_%26_Chimera_Documentation), as well as to align the inductive sensor we use for autocalibration. UPDATE: stronger base, eliminated mistake with upper fixator and bolt positioning of the previous version, useful measures in the bottom of displacement of the sensor according to nozzle. All the three components are attached in STL as well as in IPT.