Mr. Pen interlocking blocking mats come in a set of 9 mats, providing ample space for a variety of projects, including knitting, crochet, and other crafts. Made from high-density, heat-resistant, and water-resistant material, these mats are designed to withstand frequent use while maintaining their durability and shape. Each mat measures 12" x 12" with a 1" aligned grid, making it perfect for accurate measurements and consistent, precise work. The mats interlock easily, allowing you to expand or adjust your workspace based on the size of your project, ensuring flexibility. This set includes 150 T-pins, which are perfect for blocking projects, ensuring your creations maintain their shape and structure during the drying process.