This is a jig used to cut 9mm pieces of silicone tube for use with the Silicone Tube bed leveling mod for Prusa MK3 printers.
The mod is described very well here:
https://github.com/bbbenji/PMSBLM
and here:
https://www.schweinert.com/silicone-bed-level-mod-prusa-mk3/
As always, I have included Fusion 360 source in case you want to modify the design to your needs. Some people use 10mm tubes, but I find that this puts too much pressure on the heatbed, and 9mm gives plenty of adjustment.
NOTE: This jig is a remix of the concept from an original design here:
https://github.com/PaulGameDev/PrusaMK3_Silicone_Leveling
Many thanks to @Paul_GD on the “The 602 Wasteland” discord for both the idea and the original cutter design.
The author remixed this model.