With the new MK5 drive gears and smaller nozzles, the downward pressure has increased and so my old insulator retainers gave in one after another. This is a simply/quick/easy fix for that.The baseholes are widened for the bolt heads so you can use the original hex bolts to connect it to the main extruder body.I know that the newer extruders have already solved this problem but as for me, I want use the old one as long as I can. Print Clear the holes if needed Install