I used this for a custom printer's build surface; cutting it down with scissors was trivially easy. It was difficult to get it applied perfectly without debris underneath the heatbed, but I did end up getting it close enough.As far as thermal resistance goes - the adhesive performs as advertised. I've run the bed at 130C for extended periods while printing exotic materials, and the PEI shows no sign of delaminating from the spring steel sheet.The build surface itself sticks reasonably well, though it's still not great with uncooperative materials like CF-ABS. I use dollar-store water-soluble glue sticks for better adhesion; with that, it works like a charm and still releases easily upon flexing the build plate.

I had been using spring steel pei coated sheets for my bed surface but always had issues leveling my bed. Once I upgraded to a bltouch I was finally able to see why. Small parts were never really an issue but larger parts were. The bed itself was concave and more so the further away from center. Since I already had the glass sheet that shipped with my printer I thought why not try this product. The result was an incredibly flat surface by comparison and unmatched adhesion.It's easy to apply. All I did was carefully unroll the backing as I pushed air bubbles out along the way after thoroughly cleaning the glass with soap and alcohol . I've never had an issue with air bubbles, deformations, delamination etc. Once applied, I trimmed the remaining with a razor.The new surface made for some mirror like finishes on parts touching the bed. The only issue was getting the part off of the bed. The best method I've found is to force a razor blade or box knife carefully between the print and the bed. Then, push the blade further under the print until I can fit a metal spatula/scraper under the print. Finally, I move the scraper around until enough of the print becomes free from the surface. Most parts pop off of the bed violently as the adhesion finally breaks. The process isn't especially difficult but the bed gets scratched in the process. The scratches transfer to the print perfectly so that mirror like finish becomes a hazy mess of perfectly recreated blade marks. Smaller parts are easier to remove than larger parts but require the same process.Overall I got what I wanted, a cheap flat surface that holds better than plain glass. I'm now able to get my bed tolerance to less than .1 within a few minutes and that has made a big difference in my prints.

I was having adhesion issues on the stock glass bed (with texture) for the Anycubic Mega SE. I tried IPA, soap and water, saltwater film and at best was losing 1/3 of my prints, maybe more. It was time to try PEI.Installation was simple. This is like a big sticker, or the protective shield for a cell phone. I removed the glass bed, cleaned with IPA (rubbing alcohol), stuck this sheet on, and let it warm at 60 deg for a while. All this is in the clear instructions. I re-leveled my bed and ...the first print, and the next 15+ prints (still going) stuck flawlessly. Incredible. Since this was a thin sticker I did not need to change any z-offset values. The same prints that I had loaded (and were failing)Two things I noticed:1. the bottom side of all my prints are crazy smooth now. Glass-like.2. The prints are very hard to remove. Adhesion is through the roof! I found the best way was to slide an exacto knife under the print and then peel, or, knife right into the side the of the print and lift the corner. I hesitate with the scraper (metal) because I don't want to scratch the surface. Pulling hard works sometimes too (just dont't shatter the glass!)So that is a slight downside but negligible when compared to the hassles of a print not even starting! (or coming loose mid way through). Printer is running again full time. I've very pleased and will order this again if I need to.

PLA, TPU, and PETG all stick to this PEI Bed real well. The problem I am having is these filaments stick too well to the PEI surface . I've damaged many of the prints removing them from the PEI surface. On the web others say to coat the PEI surface with a layer of hair spray, Windex window cleaner, or Peanut oil to help reduce the adhesion but the prints were still a fight to get off even then. I do like the nice smooth bottom surface of the 3d print after you get it off. I even left the 3d print on the bed over night and it was still a fight to remove the print from the PEI surface.

**** Review edited after communication with seller and using item for about a month and a dozen prints or so. Original review included at end for posterity. ****I think I screwed up applying the first PEI sheet that I purchased because I did not wait long enough after cleaning the glass plate with IPA before applying the PEI sheet. This caused bubbles once the assembly was heated up to printing temperature, making the print surface uneven and requiring removal of the PEI sheet which was then impossible to reapply and made a big mess.After reaching out to the seller for advice, they sent me a replacement sheet and were very kind and helpful with giving advice on how best to get it to work for my application and clean up the mess I had made.Once the second sheet arrived, I followed the included instructions again. This time I gave the IPA ample time to evaporate before applying the PEI sheet to the glass and everything went smoothly. I also waited about a day after applying the sheet before heating it, and then let it sit at 60C for a couple hours before going to 110C to print ABS.So, how does it print? LIKE A DREAM. Going to this product from the original Elder 3 Pro magnetic surface is like night and day.First up, this over a glass sheet is completely flat! I was finally able to truly get my bed level. And best of all, I haven't had to re-level the bed in over a dozen prints.I prepped the surface with 800 grit sandpaper (didn't have the 600 that is recommended on hand) - just doing light circular scuffs over the print surface. This makes prints stick evenly and well. I've really had to try to get adhesion failure (printing a circle on it's side is still not going to work). Best of all, prints pop off cleanly once the surface cools down. Even large prints with a lot of adhered area (4"x4" for instance) pop off cleanly. I have not had any lifting up at the edges or any sagging like I used to have with ABS on the oem Ender 3 Pro surface.Cleanup is equally a breeze. Unlike the oem Ender 3 Pro surface the 3D print material does not get stuck into the rough surface. After a dozen prints the surface still looks and performs as well as on the first print. All I do for cleanup is wiping the surface down with some household IPA prior to printing. By the time the bed gets up to temp (I print at 110C) the IPA is evaporated and the print sticks nicely. Best of all, if the print surface starts having issues I will be able to renew it bu scuffing up with sandpaper again. The PEI sheet is about 1mm thick, so it will last a long time yet!**** Original review starts below. Lessons learned are not to rush and to let the IPA fully evaporate before applying the PEI sheet. ****Looks like a nice product, made in the USA. No idea how well it prints yet, since I didn't get that far.Applied to a sheet of glass (also from Amazon). Cleaned glass beforehand with IPA, (instruction sticker says to use IPA to clean the PEI sheet so figured it would be safe). Adhesive is very tacky, but I was able to get it attached to the glass on the first try with no bubbles at all (use the rolling method, like the description recommends). All was good, no bubbles at 60C per installation instructions.Went to print ABS, and got it to 110C and noticed BIG bubbles forming right in the center of the sheet, wasn't able to get them out without peeling up the edge, which ruined the adhesive throughout (torn / clumped up adhesive so the sheet wouldn't stick flat anymore).Now I've got a PEI sheet and a glass plate both covered in bits of very tacky adhesive. Not good. Going to try cleaning it off then maybe sticking it down with something else, but don't know what would stand up to the ABS printing temperatures. Will probably just have to return it... :/