This design is a modular system of bases for 27.5mm glass vial.
You can use it as bases to make sure the vials don't fall over during manipulations, use it as a  shelf to store it with a high density or as a protection if you need to transport your samples securely.
The files that compose this design are:

• Male-Female bases that assemble together
• Female-Female bases that are more compact if you assemble it with M-M parts
• Pillars (M-M, F-F and M-F) to assemble the bases on multiple floors (two different heights, 12 and 9.6 cm exist)
• A M-M join to assemble any F bases together in case you need