1″ x 121⁄2″ ruler is a great standard ruler. Offers 1⁄4″ and 3⁄16″ seam allowances. Great for zipper installations. Made of strong and durable premium quality acrylic plastic. Unique black and yellow double sight lines for easy viewing when working with light and dark fabrics. Laser cut to within 0.002″ accuracy with a smooth finish. Specially designed for right and left handed use.