1.1 1.2 1.3 1.4 For doubles, the playing surface shall be divided into halves by a white line 3 mm (1/8 in) wide, running parallel with the side lines, termed the "center line"; permanent marking of the center line shall not invalidate the table for singles play. The center line shall be regarded as part of each right hand court. 1.5 The playing surface shall be considered to include the top edges of the table, but not the sides of the table top below the edge. 1.6 Advertisements on tables are allowed only on the sides and ends of the table top and each shall be contained within a total area on any face of 200 so cm. Permanent advertisements are limited to the maker's trademark, symbol, or name once on each half of a side, but the organizing authority of a competition may grant permission for other temporary advertisements, one on each side and one on each end.