The equipment he acquired most for fun is also of interest to the rescue service.
By going deep and turning and twisting, discoveries can be made at the bottom of streams, seas and lakes all year round.
The drone has six propellers that allow it to be turned in different directions.
It is also possible to attach a claw to it, it is Leo's next project.
He has a number of non-profit assignments, including when people have been injured.
- I also have a commitment to Missing people and here the drone can also come in handy, says Leo Karlsson who lives north of Vännäs.
See the pictures from the underwater drone below the surface in the Ume River in the clip above.