3Doodler Start+ plastic filament is compatible with the 3Doodler Start+ 3D Pen. Do you want to take your creativity to new levels? 3Doodler Start+ plastic is low-heat and completely safe for kids. Bring any idea to life, or personalize your existing items with a variety of colors available in mixed packs or as single colors. 3Doodler Start+ plastic is safe to Doodle on almost any material, and can be easily removed from most materials. 3Doodler Start+ plastic extrudes up to 6 times the original length, so one six-inch strand produces over 35 inches of Doodles.