The customer service here is absolutely top notch. I thought I was having a problem with a leaking tank on my mod. They took the time to examine it, identify the problem as the coil, show me how to recognize it in the future and change the coil....even replaced the coil....at no charge and filled the tank with the ejuice I was using. I bought a pack of coils because I needed them and wanted to give them my business rather than shop online. I'd highly recommend this business