As it seems from the side, this process is very easy and understandable. But then the question arises: why the cost of PVC profiles fluctuates so if the production technology is the same for all. The answer is simple — additives introduced into the smooth mixture. The manufacture of window profiles provides for the use of more than ten rather expensive components. By the appearance of the finished product, it is almost impossible to determine their presence. Therefore, many negligent industrialists try to save on these components.