Corner Cut 2-in-1 Sewing Tool
Use this acrylic tool along with a Sewing Edge vinyl strip to mark an exact seam allowance. There are 3 seam sizes (scant, true, and generous) marked on the tool to choose from. This works on any sewing machine.
You can also use this tool to trim the dog ears on 60° points.
Instructions are included in the package and in the video below.