How to calculate the price of protective film/protective film?

It's a long story. That we just long story short. There are two algorithms for the price or selling price of the protective film: the first one is calculated by weight, that is, how much is it per kilogram? The second is calculated according to the area of the protective film, that is, how much is it per square meter? Why are there such two algorithms? In fact, it is actually needed. The protective film is generally used in some places where the thickness stability or quality requirements are not very strict according to the algorithm of how much is per kilogram, such as stretch film and stretch film, these protective films themselves are particularly good in stretchability, and their thickness will fluctuate greatly in processing. Therefore, weight is used to protect the rights and interests of customers. We sell them by weight and many scales. According to the amount of protective film calculated by square meters, it is generally a protective film with higher requirements. The flatness and viscosity are very strict, or the material of the protective film itself is expensive, and the unit dosage is relatively small, therefore, it is more accurate to price in kilograms. And some special protective films, such as high temperature resistant PET protective film, polyimide high temperature protective film (High temperature tape) The fixed length of a roll is 1mm. The quotation is based on the width. How much is the quotation. Seeing this, you should understand that the price of the protective film is so calculated? There are also some general quotation, etc. These are the ordinary business quotation methods, you know.