Bloc Loc’s Half-Square Ruler 6 1/2″ x 6 1/2″ locks onto the seam for instant ruler placement, control so that the seams end in each corner and trims 90% faster than a flat ruler. Ruler rock is gone, too! Also trims quarter-square triangles, birds in the air, y-blocks, LeMoyne Star, double windmill, hidden squares and much, much more. HST ruler is multiple-sized and trims in 1/8″ increments.

Note: You can cut any HST up to 6 1/2" with this ruler.