PLA (Polylactic Acid) filament is a thermoplastic monomer that is derived from the fermentation of renewable, plant-based materials such as corn starch and sugar cane. It is only compostable in an industrial facility and does not biodegrade on its own.

PLA is often marketed as compostable, but it is only compostable under specific conditions. It will not biodegrade without the help of industrially prouced composting equipment and heat.This Flexi-Rexi design is an open-source design by Dr. Lex shared under the Creative Commons - Attribution - Share Alike license. It is a remix of Kirbs' Flexi Rex (Thingiverse thing:1759297), based on airfish's remix (Thingiverse thing:2189652). That model in turn was most likely inspired by the ‘Flexy Rex’ by zheng3 (Thingiverse thing:929413).