Borosilicate Glass or PEI with spring steel backing (if your bed has the magnets vs the build surface having magnet material) work great in my first hand experi

Borosilicate Glass or PEI with spring steel backing (if your bed has the magnets vs the build surface having magnet material) work great in my first hand experience, both will give a much better surface adhesion than most others. Another cheaper option is G10 or FR4. I've got copper backed FR4 on my list of things to try. Apparently it has a more even heating due to he copper against the heated bed. I've been using the glass held on with Binder clips until recently when a few binders popped off and tossed the whole lot on the floor of my garage sending shards everywhere.