Use our 4 mil virgin 'Ultra Clear' poly when total transparency and clarity is preferred. Ultra Clear is ideal for winterizing windows; you can still see through clearly while the 4 mil plastic reduces your heating bills. Our Virgin Poly Sheeting is made from non-recycled resins, allowing for maximum clarity. Virgin vs Regrind: What is the difference and why is it important? Virgin poly pellets are brand new pellets – never been used before. Regrind pellets are made from melting down used poly and then made into pellets. This used poly can come from many different places and things such as plastic bottles, old tarps, plastic bags, etc. They come from just about anywhere from households to commercial sites during demolition. While recycling is good for our planet, it’s not always the best option for poly sheeting. If you need to put plastic on the ground for landscaping to keep the weeds down, go ahead and use recycled plastic. On the other hand, if you’re putting in a vapor barrier or shrink wrapping something important enough to keep it in a weather-proof wrap, then you might not want a poly made from regrind. Regrind pellets could have dirt, moisture, or other foreign materials in them.