3Doodler FLX01-Black Plastic 3D Printing Pen (X25 Strand), Flexy Black Take your creativity to new levels with Flexy! do you want to take your creativity to new levels? no longer are you bound by the rigid constraints of hard plastic! Squeeze, stretch, & twist! with our Flexy line you can now squeeze, stretch, and twist your creations providing a truly dynamic doodling experience. Flexy plastics are compatible with the 3Doodler v.1, 2.0, and create 3D printing pens. Explore the wide variety of Flexy plastic refill colors including clear! available in single & mixed color pack containing 25 strands each, and single colors tubes containing 100 strands.