Acmer lasers have a tapered foot that lends itself nicely to extenders which auto-center and are not prone to wobble. These are 47mm extenders, and can be stacked. They also work nicely to add 3/4" real rubber feet which are needed to keep the laser from sliding during high speed operations on slick tables. If you print these at PrusaSlicer's .35mm speed setting they SNAP together nicely as well! Enjoy!