This is a great multi-purpose tool.  When I first saw it, I knew that I had to have one, and I haven't been disappointed yet.  The most useful application for me has been in concrete formwork. Quite often the lumber  that we get on job sites is badly twisted, either from poor quality or  exposure to the elements.  The tweaker makes otherwise troublesome and/or  useless lumber useful again.  Also when forming tilt-wall panels or curbs  with 2x material, this tool is a must have, and replaces bulky job-built  devices that can only be used to "tweak" the boards, but do not  have the added advantage of pulling nails also.  Great buy.