After finding that my prints were coming out slightly curved on the Flexplate face, I purchased Micro Porous Glass for an Ender3 from Amazon. The glass comes with an adhesive on the back and is $12.99. The Glass is 235mm x 235mm x 4mm thick. I purchased an addition flexplate plate that is 235mm x 235mm. I put the glass on the plate. It is slightly oversized but works fine. It gives me nice flat prints. The plate must be slid on and off because the magnets are too powerful to lift it off. 20200325 I just tested the auto level with the Partsbuilt board. It worked very well. I use circles when setting the offset and never got real good leveling before. The glass plate gave me perfect circles. The auto level went from useless to a very useful tool.