🎁【Advanced Technology】 This pen has been designed with advanced obstruction mechanism technology to prevent jamming. After leaving, the 3D wire is automatically retracted to prevent it from jamming. Residues are automatically excluded. Automatic sleep when not used for about 5 minutes. 🎁【Standard Size Friendly Material】 Two modes compatible with 1.75mm PLA and ABS filament. The refill is standard size so you can purchase extra filaments when it runs out. The 3D pen is made with skin-friendly materials and the PLA material is non-toxic and odorless. 🎁【LCD Display】The LCD display will not only show the types of material you’re using(ABS or PLA), but also will display the temperature. So it becomes easy and convenient for you to get control of this 3D pen. to avoid jamming. Residues are automatically excluded. 🎁【Much Safer】It comes with 2 finger protectors to cover your thumb and index finger to avoid hurting during use. Since the tip of the pen will become hot while the pen’s working, it’s required children should use this pen under adults supervision. 🎁【18 month warranty】 Supported with 18 month free replacement warranty and 30 day no refund reason. If you have any questions about the 3D pen, don't hesitate to contact our customer service.