This product is a complete waste of money and time for anyone in the automotive welding industry.Using this product, our team found that it fails to clean the solder properly and leaves behind a lot of residue. Not to mention, the sponge is cheap and quickly falls apart causing more mess than it solves. The only positive thing about this product is that it is inexpensive, but it`s not worth it even at that price. Avoid this product if you value your time and vehicle's maintenance..