Stressfree

1   weight 6 ping pongs with another 6 ping pongs. see which side is heavierTVBNOW 含有熱門話題，最新最快電視，軟體，遊戲，電影，動漫及日常生活及興趣交流等資訊。! B  f1 g) T1 z
2   spilt the heavier side ping pongs in half and weight against each othertvb now,tvbnow,bttvb7 X4 z3 e9 X  d2 `
3   weiht either ping pongs one on one then you will know which is the heavy one.