I already knew how good the product is and had been purchasing from Zep. I have seen this product used in just about every auto repair shop I have worked in and now that I have my own repair shop (Golden Auto Repair 512-989-0898) it is all we use to clean the oil and dirt from our shop. We have been told by many of our customers how clean our shop is. Also the cost from Depot is about half the cost from Zep.