although small, a steelyard weight may tip a hundred pounds (idiom); apparently insignificant details can have a large impact; for want of a nail the battle was lost
齿条千斤顶齒條千斤頂chi3 tiao2 qian1 jin1 ding3
rack and pinion jack
公斤公斤gong1 jin1
kilogram (kg)
斤斗斤斗jin1 dou3
variant of 筋斗
斤斤计较斤斤計較jin1 jin1 ji4 jiao4
to haggle over every ounce; (fig.) to fuss over minor matters; to split hairs