These time saving mats fit neatly into full size sheet pans, or can be used as work mats on counters. Can also be placed under cutting boards to keep boards more stable during use. Food Grade Silicone over reinforced fiberglass to withstand temperatures up to 480°F (250°C). Printed measure marks for easy size reference in inches or cms. Naturally non-stick, reducing need for fats or oils. Safe for use in oven, freezer, or microwave.