USA Made. Non-slip square up rulers with easy-to-see blue and white translucent markings. Use our SpinAbout by QuiltCut feature to spin the ruler around 180°, allowing you to easily add a 1/2 inch seam allowance to your cut pieces. Dual colored for use on light and dark fabrics with exclusive invisible line windows allow you to see the edge of your fabric for easy alignment. 45° square up diagonal with size indicators and square up guidelines to square up blocks and trim half squares, and white centering lines to fussy cut blocks. Accurate 1/8 inch measurement scales are printed across the top and bottom in both directions, allowing for right and left hand use.