1、Robust design, easy to load, quickly find the required information, clear at a glance, no need to extract, simply flip through to find the desired information 2、One button to prevent accidental dropping, waterproof and anti-fouling to protect your data, wear-resistant and fold-resistant, hard cover to prevent data damage 3、Easy to handle without scratching, and you can use it more assuredly. Encrypted webbing edging, thickened handles to prevent hands from being scratched 4、The overall edging, anti‑collision, large rounded edging design, 13 layers of large capacity, about 150~200 test papers, can hold about 300 A4 papers or about 150+ test papers 5、Easy to store, it can be put in most schoolbags without taking out as a whole, and it is also convenient to get information