I have used a pump on my kayak and it has worked fine 3 times. When I tried to charge it the fourth time, the battery would not accept a charge. I tried to get help from customer service. They answered my first emails and then stopped. No help was given. Now they don't reply to my emails. I have another pump model from the same company and it works great. Conclusion: I'm not sure I would buy anything else from them. In my experience half of their products stop working after a few uses and their customer support only responds when they ask them to. Update: It's been a few weeks. The company emailed me several times. There was no help but they asked me to remove my negative review.