Two of the five in the package were non-functional. They have been opened, labels removed and are not working properly. **Update** ELECTECK staff contacted me about the issues with my product and quickly and promptly apologized for the shipping error. They have since provided additional working parts for those with problems. Overall I received a great product at a great price. Yes, we had an initial problem, but the interest in doing things right counts. Working with someone who cares about your experience is going well, that's all I can ask. Thanks very much!