Where to buy HDPE (suggested top of box material)?

Question

Hey, everyone says "get some HDPE for your box project" So I'm wondering, where do you get this stuff?

Answer 1

from premade boxes

Answer 2

Most cities of any size have a plastic and engraving store - they will carry it in sheets and may even have strips or be able to cut them for you.

Someone else suggested that plastic decking (is it Trex?) that is made out of recycled HDPE. I would also look into that at a home supply store if you can't find other source.

Good Luck