The Sew Trim 5.5" HST Ruler is a speciality ruler to square up half-square triangles!
With this ruler the blocks do not need to be open before trimming instead, you trim the blocks down before opening them up. This means you will only make two cuts instead of four, making it faster and more accurate.
Place the line on your sewn line with the indicated size that you want. Trim the edges and presto! Your HST is square and ready to be pressed.
Finished block sizes from 1" to 5".