What are the reasons for the large price difference of 3M light box cloth film?

I want to be a 3M light box door, so I searched several companies like 3M on the Internet, thinking about comparing prices, but I don’t know that the prices are very different? What's happening here?

What are their differences, leading to a large price gap. . . .

One, the material is different

Inferior 3M cloth, with soft texture, thin thickness, low tear strength, and no difference in hand feeling with ordinary light box cloth. The authentic 3M light box cloth feels firmer and thicker when held in your hand.

Two, the use period is very different

Compared with the price of genuine 3M light box cloth, inferior ones are much cheaper, but the service life is also very different. The genuine product has a three-year warranty, but it can be used for 4 to 5 years, while inferior quality fabrics have no quality guarantee. If you are lucky, they can be used for 3 years. If the quality is worse, it will only be 2 years.

Three, in terms of lighting effect, the effect was good at first, but after a while, the inferior 3M cloth will be revealed.

As mentioned above, low-quality cloth is soft and has low tear resistance, so it is not resistant to outdoor cold and strong wind. The strong wind often blows, and the picture oscillates back and forth, and the ductility is poor, which causes the picture to be uneven.