Abstract: A floor mark used for a sport game is painted on the outer layer of a mat unit. A pair of mat units to be laid adjacent to each other are fastened together by means of a slide fastener. This slide fastener has a pair of fastener tapes, and a slider to be fitted around the guide sections of the paired fastener tapes. The fastener tape has a length substantially equal to that of the mat unit, and is covered with the outer layer throughout. Each fastener tape has a non-tooth guide section and a non-adhesion section which is not adhered to the outer layer. The non-adhesion section extends from one end of the fastener tape, and is longer than the non-tooth guide section. A positioning mark, used for adjusting the positions of the floor marks painted on the mat units, is painted or written on the surface of the fastener tape, such that the positioning mark is within the range of the non-adhesion section.