Abstract: An element for use in making a playing surface, particularly an out door tennis court. The element is, for example, a square of 10 cm side, two sides having hooks and two having loops. A series of elements can be laid side-by-side with a hook of one element engaging a loop of another. The hook and loop provide for contiguous location of the elements while allowing for slight movement between the elements. Thus, the elements can expand in hot weather and contract in cold weather without adversely affecting the playing surface.The element has a cellular structure. Each cell has inclined faces converging towards an aperture. The inclined faces of adjacent faces come together towards the top along a line which forms an intangible upper plane. The lines have a rounded crest. Thus, rain which falls on the playing surface will run down the inclined faces and drain through the apertures of the cells leaving the playing surface free of rain water.