Calibration Stairs!
for SLA printers

mainly to check for overexposure on your first layers
stair platforms are 4xx4mm
the heights from the base should be
0.5mm
1mm
2mm
3mm
5mm
10mm

the small circles should indicate overexposure if too thin

dimensional accuraccy can be measured with the two things on the side
they should have 8mm inner and 16mm outer distance