My son spilled "something" on his carpet and never told me about it. By the time I discovered the stain, it was set. I tried numerous stain and spot removers but none of them worked. I used the Shark StainStriker on the same large stain, and after two applications, the stain was completely gone!! I couldn't be any more happy with this device. I then used it on a set stain on the backseat floor of my car, (seeing a pattern here) and it also removed the stain after only one application. The StainStriker works as advertised, only con to this device is that it slightly "leaks" around the hose seal and your hands get wet, other than that, I highly recommend this product.