A 3 point headtracking device to be used with FreeTrack ( http://www.free-track.net/english/ ). EDIT: Use FreeTrackNoIR, it's the successor of FreeTrack (even supports headtracking without an IR device!): http://facetracknoir.sourceforge.net/home/default.htm Includes a battery compartment and a opening for a switch. Designed to be put on top of a headphone. If you have a Logitech G930 you can use my clip for the G930 to attach the device to your headphone: http://www.thingiverse.com/thing:47124 (use one with center guides). Or just use velcro tape, or design your own clip :-) Additional Parts: -2x M3 screws (10-15mm) -4x M3 hex nut -3xLEDs, some electronics, 2x AAA batteries Credits: The battery holder is based on this thing: http://www.thingiverse.com/thing:5079 Thanks obijuan!Print one holder, one tail, one lid Solder a cable on the corner of each hex nut Put the nuts into the battery compartment, with the cable going through the channels in the nut traps Solder you LEDs, put the cables and leds in the arms and the tail Solder the cables,switch and electronis inside the main box Put batteries in Screw screws in Switch on