Scribbles, lines, curls, swirls...drawing anything that comes to mind can be a lot of fun even if you are not particularly gifted with drawing skills!
Doodling pens are the traditional tools for drawing but ink is not the only option as you can also draw with plastic, the same way 3D printers do, by using a 3D printing pen such as the Tecboss RP500A 3D pen.
The Tecboss 3D printing pen is a very cool bit of drawing kit that works like a doodling pen but instead of drawing ink, the Tecboss 3D pen draws melted plastic via a heating element integrated in the 3D pen. This particular 3D pen uses 1.75mm PLA only filaments which means, you cannot use ABS filaments with the Tecboss 3D pen because the 3D pen does not heat up above 80 degrees; hence it won't be able to melt the ABS filament.
While you are limited to PLA, this type of filament does not give off bad smell like ABS filaments do; hence you won't need to ventilate the room. 3D printing pens typically use ABS or PLA thermoplastic instead of EVA thermoplastic sticks used by hot glue guns. While hot glue guns work a bit like 3D printing pens by melting plastic and extruding it through a nozzle, you can't properly draw with a hot glue gun like you can with the Tecboss 3D printing pen.
The Tecboss pen is handheld and even though it has a squarish-rounded shape it is comfortable to hold in the fingers for a long while. Holding it feels like holding a chunky pen but it's precise enough to for meticulous work.
Something else worth highlighting about the Tecboss 3D pen is the sleep mode safety feature which automatically powers off the 3D pen after 3 minutes of inactivity. Sleep mode is a feature you normally get with rechargeable devices and even though the Tecboss RP500A 3D pen is not rechargeable, it is a useful safety feature to have because the ceramic nozzle of a 3D pen gets extremely hot.

You don't want to lay the 3D pen on a surface that can catch fire and you don't want to leave it laying around unattended because someone picking up the pen from the hot ceramic nozzle will burn themselves (I can testify to this!). Make sure to place the Tecboss 3D printing pen into the pen holder provided.
The Tecboss 3D pen casing is made of matte black plastic with the DC power socket and filament loading hole located on top of the unit.
The bottom of the Tecboss 3D pen features the ceramic nozzle and heat vents. There are four leds on the 3D pen, one of which is a power indicator light (bottom led).
The top three amber leds are the indicator lights for the feeding speed which can be slow (bottom led), medium (middle led) and fast (top led).
You get a total of four triangular-shape buttons, two on the front and two on the back of the unit. The front triangular buttons unload the filament (top button) and load/heat the filament (bottom button).
The triangular buttons on the back are for controlling the feeding speed of the filament from slow, medium and fast speed.
While the Tecboss 3D printing pen does not integrate a rechargeable battery, it can be powered from a wall electrical socket and a portable charger.
The Tecboss 3D printing pen is powered via 5V 2A input so you will need a power bank with similar rating. Most power banks output at least 2A so any will do. A few powerbanks worth checking out include the ElecJet Apollo, Xtorm XB201, Askborg chargecube and the Anker Powercore II
Once the filament is fed into the pen, you can adjust the speed. When you are done using the pen, press the unload button to unfeed the filament out of the pen.
Included with the Tecboss RP500A 3D pen is a UL certified USB power adapter, a USB cable to DC barrel connector and user manual.