MYNT3D Professional 3D Printing Pen with OLED Display - Perfect for DIY Crafts, 3D Art Projects & Home Decor Creations

I love this pen, it's fun and simple to use. It feels a little clunky at first, but once you get used to it and learn how to control it it's easy to use. The cord is a bit too short though.You can't load the filament into the pen until it reaches the set temperature. It heats up pretty quick, so once it reaches the temperature you've set it to you can load the filament. Just hold the arrow button that's pointed at the pen's tip as you put the filament in. If you set the pen down for a couple of minutes it will start to cool down as it goes into a standby mode (it still stays quiet hot though so don't touch the tip to anything). If it drops temperature you can't use it, nor can you unload the filament. To heat it back up to the set temperature just push the arrow pointing at the pen's tip once and it should heat back up.Plugging the cord into the pen first then into an outlet sometime the pen doesn't come on, but plugging the cord into the outlet first then plugging it into the pen hasn't caused any issues.