Prusa i3 MK2 induction probe converter

I had several LJ12A3-4-Z/BY induction probes, but unfortunately the size is a mismatch with Prusa's excellent new extruder for the MK2. This converter can be bolted onto the usual induction probe holder to allow the use of 12mm probes. With some work, it should be easy to convert it to also use 18mm probes.

Simply use a piece of 8mm threaded rod or such to keep in place.