Do you think the semi-trailer 6 or 6 is better than 4 or 2?
See how many tons of goods you pull, 6 times 4 can pull 55 tons, 6 by 2, you can pull 51 tons!
Of course, * 4 good strong and not easy to be stuck to.
That depends on how much you pull the goods, the 6 multiplied by 4 from the heavy point, 6 by 2 of the self-respect, easy point, the difference is that excessive station fees.
