Flow (E multiplier) Calibration Cube Shape

20x20x20 cube type shape includes:
10mm radius on one corner
45 deg chamfer on one corner
45 deg overhang
cutout in floor.
walls have 0.8 mm thickness
base is 1.0 mm thick

I used it to calibrate my flow settings as well as z steps.

Nice step by step here by e3d:
https://e3d-online.dozuki.com/Guide/Flow+rate+(Extrusion+multiplier)+calibration+guide./89

I measured all 4 flats and center of the radius then averaged the value.