Precise Measurement: Each ruler features a non-slip surface with 1/4in seam allowance and marked points for easy, accurate positioning. Measurements are taken from point to point for professional precision. Heat-Resistant Material: Made from premium resin plastic, safe for continuous use up to 428°F and short bursts up to 536°F. Works with dry or steam irons to press hems, folds, and seams accurately. Heat-Resistant: Withstands temperatures up to 428°F/220°C and tolerates short - term ironing up to 536°F/280°C. The ruler will remain hot for a few seconds after ironing. Translucent Design: See fabric underneath for precise placement. Fold fabric over the ruler to the desired hem depth for faster, more accurate pressing. Versatile Shapes: Includes 5 shapes—Hexagon, Pentagon, Diamond, Triangle, and Circle—for ironing different fabric patterns. Each ruler measures 2 inches for detailed hemming and crafting.