【Precise grid and circle guides】: Blue grid lines and orange concentric circle guides make it easier to align straight edges, corners and round projects for even, symmetrical blocking results. 【Secure interlocking fit】: Precisely cut puzzle edges connect securely to create a stable blocking surface with minimal gaps, helping your project stay flat and properly positioned. 【Flexible 4-piece layout】: Each needlepoint blocking mat measures 12 x 12 inches. Use one mat for smaller pieces or connect all four mats to create a 24 x 24 inch surface for larger knitting and crochet projects.