After much testing, this is what I believe to be, the best filament clip out there.

When it comes to storing your filament, if you apply too much or too little pressure your filament will become brittle over time and snap, even when stored in what you think are ideal conditions. Multiple youtubers have brought this to light and the solution is to buy a strap or band to hold them in place under the right tension. Well here is my very simple and low filament cost solution.

When Printing:

Two sizes available, one for hard plastics like PLA/PETG and a larger one for softer plastics like TPU that are harder to push through. And a model that has the holes at exactly 1.75mm in diameter, adjust the hole contour on the object to your printers tolerances (like 0.45mm) clone to how many copies you want and print.

Use:

Just slide the filament thought one hole, and then loop it around the spool and put the end through the remaining whole. Pull it tight, it's as simple as that.