Clear seam guide for adding a precise 6 mm (1/4") seam allowance to templates and marking stitch lines on pre‑cut pieces. Rigid design supports rotary‑cutting layouts and quick measuring on patchwork units. Useful for half‑square triangles, flying geese and garment seam allowances. The slim profile fits in project bins and rulers, making it a simple, accurate tool for piecing, pattern alterations and quilt assembly.