This is a super easy and fast to make tool and it is 100 % recycled.
This water level is really useful for example when you need to paint a room of two different color horizontally, or you need to find the same level of two things far apart from each over, like two shelfs, or two paintings.
Step 1: WHAT YOU NEED
You only need two small transparent plastic bottle, a used bike tire (without any holes) and a pair of scissors.
Step 2: CUT THE BOTTLES
Cut the bottom part of the plastic bottles.
Step 3: CUT THE INNERTUBE
Cut a piece of the inner tube, long as you need it.
Step 4: ASSEMBLE IT
Place each open side of the inner tube in each neck of the bottles (like in the photos)
Step 5: FILL IT WITH WATER
Fill one of the bottle with water, keeping the inner tube without any fold and the over bottle at the same level.
Step 6: DONE
Is easier to use in two people (or otherwise you need to make an hole in one of the bottle and hang it up on a neil on the wall).
Hold them both FIRM on the wall for few second and mark the water level with a pencil.
The water level is always constant (communicating vessels principle).