^ x2
36 minutes response time. And it wasn't even critical!
Printable View
If you want some thing that is more accurate than the bubble level and displays in degrees you might look for some thing like this.
http://s7.sears.com/is/image/Sears/0...sm=0.9,0.5,0,0
Johnson Magnetic Angle Locator - Model 700 at Sears.com