Wisehands 3D Pen Filament Refills Printing Drawing Plastic Pack of 20, 39.37 Inches Each The diameter of the strands is 6.9 inches for 39.37 inches length. The temperature range for this product is 190C - 220C. These are projected spec and they may vary with the pens and printers. The 20 different colors which come in the package including 4 glow-in the dark filaments to give you more options to create your masterpiece. We decided to create a large variety of filaments so you will be able to give more details to your 3D piece of arts. 787.4 Inches of 3D printing drawing plastic filaments. With this amount of filament length your masterpiece project is limitless. This package comes with 20 strands of 393.7 inches each. We provide you the highest quality material for your 3D masterpiece. Our strands are made of premium material and have a round shape diameter providing the perfect through the pen or printer. The strands can be used in 3D pens and printers. The different strands can be used for all types of 3D printing and are perfect for detailed art.