Vacuum is highly important to windshield repair because the high vacuum cleanses the broken glass to be repaired. In an average repair where vacuum isn't used, resin reacts with air and moisture to produce negative effects to the resin. With all the available information concerning the importance of vacuum in high levels it is almost stupid to contest the importance of high vacuum. Vacuum is used in many applications in today's world, (see our link) and is just as important in Windshield repair. Windshield repair and vacuum injection molding are pretty much one in the same. This can be shown on another link for free patents online. Applying a high vacuum to the damaged glass first allows for moisture to leave the damage as well as any air. The high vacuum helps the resin seek out any nooks and crannies to obtain more complete fills to the damaged glass. Vacuum lowers the amount of time needed to complete a repair. Many systems on the market especially several of the newer "vacuum" systems" apply vacuum first but only at a very low vacuum. They are producing anywhere from 17 inches of mercury to 21 inches of mercury. Our system the Super Cinch produces around 28 inches of vacuum, while suspending the resin. The higher vacuum levels produce cleaner, faster and more purified repairs than any of our competition. Some newly announced systems producing 21 inches of mercury compared to our 28 inches are of no significance in being a better windshield repair tool. Our vacuum specialist who works for the military says the higher the vacuum the better. He says systems that produce lower vacuums than our tool are not even close to the benifits provided by using higher vacuum. In some older vacuum units first introduced with using a power vacuum pump with a long tube connected to a cup fitting over the glass damage was the right idea, but with a serious flaw in the design. In damage that is notably weaker like stars and angle-wing breaks pulling nearly all the air from under the cup produces a significant amount of additional weight to the glass and in many cases forces the glass to be damaged further. It is also note worthy to realize that to actually evacuate the damaged glass, the pump used to evacuate the damage needs to send the air out of the device. Closed systems do not evacuate the air and certainly none of the moisture. Resin must be held up and away from the glass for moisture to be removed from the break. Any resin left on the glass will block moisture from getting out of the damage. Resin will act as a barracade for moisture. Please read the links concerning vacuum injection molding and links to our vacuum links for more verification concerning the importance of vacuum.