This OLFA® square ruler is super big.  I use it to square up quilts as it gives me such a huge square I can be confident that it’s a 90° corner.  It is easy to read, with its black numbers on the frosted background.

And the ruler is easy to use, with its non-slip surface.

The ruler is great for squaring larger blocks, borders and for square designs.

I square up my quilts with this ruler – here’s how I do that.