I have more than six of these cassettes. Its small size fits easily in a pocket and its length is sufficient for most jobs. I have one in my kitchen tool box, one in my truck, one in my office and a few lying around in my garage and workshop. Although I've used them for years, I've never worn them out or broken them. I did however buy a few extras in case they stop making them. I do not want to do home repairs and work with wood if there is no such person around.