American ASTM Agency recommended the school bags’ size and weight:

1. Height more than 30cm, can put in A4 paper

2.Weight do not exceed 15% of the child’s weight

?Schoolbag Recommendations:

1.Weight do not exceed 15% of the child’s weight

2.Widening high elastic sponge strap can protect the Cervical spine and shoulder

3.Putting the large and formation articles in the closest position to the back is effective way to relief.