Amazon.com: Kingroon Filament Dryer Box for The 3D Printer, 3D Printer Filament Dry Box Keeping Filament Dry During 3D Printing 4L Compatible with 0.5/1KG Filament and PLA Filament and PETG TPU ABS
Reprap development and further adventures in DIY 3D printing: DIY Heated DryBox for 3D Printing filament - under $20
DIY Active Heating Filament Dry Box : r/functionalprint