Polymaker PETG Filament 5kg Grey 3D Printer Filament, PolyLite PETG 3D Printing Filament, Dimensional Accuracy +/-, Print with Most 3D Printers

The most engineering-minded consumer brand in this space. Polylite is their everyday PLA, PolyMax adds impact resistance, and PolyWood nails the timber look. They publish data sheets and actually explain what's in their formulations.