Used with common digital calipers to verify if print bed is level. The jig is designed for 8mm gantry rail - average 51.3mm apart (Rigidbot). Various digital calipers seem to be rebrands from a same manufacturer; but verify if your caliper will fit before printing. See instructions for additional info.A support piece with holes should be removed after printing. Slicer: Support Off Infill 20% Use some form of platform adhesion, else rail channels will curl up as the part cools and shrinks.