I bought this one last year (It was a few bucks cheaper then) and it works fine with the 9v ripcord on the 404 and 303. I also have another old no name 10,000mah bank that works with it. So, I imagine you could find something cheaper. A 2-3 hour beat making session doesn't put a dent in the 25,000mah bank. You could probably get 12-14 hours out of a full charge.