I had bought this gadget months before unsure how to use. When I went to class on Saturday the teacher demonstrated how to use it. Works really great.
It is called a Precision Trimmer 6" helps perfect your piecing and made by Marsha McCloskey.
Here is the website for it
http://www.marshamccloskey.com/rulandnot.html
Pic of the ruler
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2nd pic of the ruler
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