A pen that creates sculptures in mid-air is being billed as "the smallest 3D pen in the world."

Lix is an aluminium pen just 16.5 cm long that works with ABS and PLA plastic filaments to create 3D sketches at the touch of a button.

The pen is plugged in to a power outlet via USB and charged for one minute -- the time it takes for the filaments to reach to optimum temperature to melt the plastic.

The temperature at the pen's output is 202 degrees Celcius, allowing the melted filament to be completely guided by the drawer's hand.

The design also features two speed control buttons for more precise creations.

Depending on the filament inserted, users can create real-life drawings in a range of colors and glosses.

Lix is not the first 3D pen on the market, but developers argue that it is the smallest and lightest, allowing for a freer drawing style.

Following a campaign on the crowdfunding website Kickstarter, the pen will retail for $139.95.