Take your 3D printing pen creativity up a notch with these amazing inks. Build sparkling objects with glittering ink, or glow-in-the-dark shapes. You can even experiment with heat sensitive ink that changes colors with the temperature. The UV light inside the pen cures the ink as you draw, hardening each line and letting you build almost immediately. And, because the ink stays cool (unlike with other 3D pens), it's safer to use.