Those levels are useless on an un-level floor, and its rare to find a surface thats level.
The most accurate method is this.
![[Linked Image from media.doitbest.com]](http://media.doitbest.com/products/327921.gif)
Although due for a re-design so you can read it from the side....
And, I have only one complaint about the Greenlee 1/2", the foot stop is too small, you can't get a steel toe in there for proper foot pressure.
Person favorite is Ideal cast iron.
