These scrubbers have changed my life. I was too ambitious and built 12 RC hobby cars over the course of about 3 months during the 2020 mandatory lockdown. As the months went by my need for solder repairs/rebuilds became overwhelming. My solder joints looked shit then and also conducted. This was when I used a damp sponge to remove corrosion from the tips. These sponges gave me the confidence to continue this exciting hobby. I'm not saying I'm the best solderer, but I'm the best solderer I've ever been!