LulzBot  Taulman 645 Nylon 3D Printer Filament, 1 lb. Reel, 3 mm, Natural Hot-end print temperature 240-250C Adheres well to heated glass, PEI, and PET print beds coated with common glue stick or aftermarket Garolite print surfaces Nylon 645, like many polymers, is hygroscopic meaning it absorbs moisture. It is very important to keep 645 dry to achieve good printing results Nylon 645 can warp significantly as it cools. Use of brim in your slicing software can help keep the object flat on the print bed