This bracket is designed to be used on ord bot hadron with QU-BD extruder. is to be assembled right on the 40mm cooling fan The servo used is a Towerpro sg90. for Z-probe, use a micro switch.The bracket will fit right on 40mm cooling fan that comes with QU-BD extruder. You just need to buy some longer M3 bolts to mount the bracket. The hole where the servo to be mounted is intentionally made ??with interference fit. You may need to adjust the hole some if it is too tight. on the probe_40mm_PC_FAN_MOUNT there are 2 points that are supposed to used with cable ties to secure the cables that go to the servo and microswitch Software is not my strong side, struggling a bit to get it to work. If there are anyone who have marlin firmware for ord bot hadron set up with auto bedlevel and want to share / help me get it to work it would be much appreciated