: Fix the prices according to the length. In that way,the total price can be easily calculated.for the design institutes who provide the copper strand conductors also calculated as length.

No.2: Fix the price according to the weight, which is fair to the purchasers. For the manufacturers buy the raw materials by weight, then they sell out by length or weight after processing. As fact, there is no difference between using length or weight to pay a price if  manufacturers follow the production rule and act honest.