Allows drawing properly-directed belts like tiles. Draw belts with a single drag!
There is a tutorial in scenarios.

Demonstration: https://www.youtube.com/watch?v=Za5ZuAONRUY

Usage:
- Craft "Belt brush"
- Decrease the belt brush set size to 1 (Numpad-)
- Draw 5 tiles to make it work

Belts: drag in a required direction
Underground belts: drag through built entities
Splitters: move mouse 1 tile back diagonally and drag again