Based on the Gridfinity system by Zack Freedman.

This is a simple 1x1x4 holder for soda bottle preforms (aka "blanks"). They're what soda bottles look like before they're heated and inflated to their full 50/50 sucrose/glucose fluid containing ultimate form. They're also handy for holding small tools (tweezers, nozzle cleaners, acupuncture needles, etc.) and parts.

This design doesn't hold the preforms too tightly so they can be grabbed easily by students, makers and the rare soda preform collectors out there. Enjoy!