specification         gender junior high school (12 - 15 yrs) senior high school (15 - 18 yrs) university students and adults (18yrs + )
0                maximum length  male & female                           114 cm                           117 cm                                    120 cm
1                minimum weight           male                            440 g                            480 g                                     510 g
2                minimum weight         female                            400 g                            420 g                                     440 g
3  minimum diameter of sakigawa           male                            25 mm                            26 mm                                     26 mm
4  minimum diameter of sakigawa         female                            24 mm                            25 mm                                     25 mm

Table as JSON:
{"specification":{"0":"maximum length","1":"minimum weight","2":"minimum weight","3":"minimum diameter of sakigawa","4":"minimum diameter of sakigawa"},"gender":{"0":"male & female","1":"male","2":"female","3":"male","4":"female"},"junior high school (12 - 15 yrs)":{"0":"114 cm","1":"440 g","2":"400 g","3":"25 mm","4":"24 mm"},"senior high school (15 - 18 yrs)":{"0":"117 cm","1":"480 g","2":"420 g","3":"26 mm","4":"25 mm"},"university students and adults (18yrs + )":{"0":"120 cm","1":"510 g","2":"440 g","3":"26 mm","4":"25 mm"}}