A simple remix with a slightly larger hole to fit M4 suction cups. I used 40 (yellow) and 50mm (red) suction cups, and both are very strong when attached to a smooth surface. Here are the cups I got from Amazon (affiliate links): 40 mm suction cups 50 mm suction cups Printed with Sunlu filaments with my Anycubic Kobra Neo.
Download from thingiverse