Joint mats There are 16 light beige mats and 18 brown mats, for a total of 34 mats. The size is approximately 30.5cm x 30.5cm (including one side of the interlocking tabs). The thickness is about 7mm. They were used for childcare, so there are scratches and stains on both the front and back. Please see the photos for the typical scratches and stains on the surface. Please understand that these are used items.