Due to the inertie caused by the speed of machine operation during the manufacfacturing of zipper as will as the completeness of the teeth, there will appear allowable tolerance.
Kwa sababu ya kutokuwa na nguvu kunakosababishwa na kasi ya operesheni ya mashine wakati wa utengenezaji wa zipu kama itakavyokuwa kama ukamilifu wa meno, kutakuwa na uvumilivu unaokubalika.