3D Pen Filament Refills - 2 Pack Bundle with 40 Strands Per Package, 80 Strands in ALL - 66FT Long for 3D Printing - 1.75MM PLA Eco-Friendly Plastic - FREE BONUS Stencil Ebook ( Bright Magenta ) "Limited Time Offer: 50% OFF on Sale Price. (Enter code EEEJ2EWR at checkout)."BETTER FOR THE PLANET: Our 3D doodle pen refills are made out of PLA, a type of plastic made from Corn that is biodegradable and free of petrochemicals SMOOTH INK FLOW: 3D Printer and 3D Print pen refills allow ink to move easily thought the extruder and nozzle to write smoothly and evenly. 3D printer filament 1.75 mm. Not for 3Doolder Start Pen which use 3mm material. UNIVERSAL DESIGN: Our 3D printing pen refills measure 1.75 millimeters in diameter and are 10 meters long to fit most standard 3D doodler pens STOCK UP ON SUPPLIES: Special 2-pack set gives you a total of 80 3D Pen filament refills for an amazing price FREE BONUS EBOOK: 2D, 3D and wordart stencils for beginner's practice. Ebook in pdf format will be delivered to your email inbox.