FreeCaliflower (my free version)
Printables
7 model
Free
Free100mm dimension calibration tool (aka Califlower)
Printables
FreeCalistar - Parametric, open source alternative to Califlower
Printables
FreeCalitower Z - An addition to the open source Calistar
Printables
FreeCalibration Rings (CaliRings)
Printables
FreeCalibration
Printables
FreeThe Corsair Calibration
Printables