My first experience with e-stim is from this box! It's absolutely loads of fun and I'm eating through 9v batteries like candy now. It's given me lots to tinker & experiment with. Trying different pads & loops and their placement, tri-phase setups etc... Only a few minor gripes. The cables are very stiff, and one of them had a loose internal connection where it connects to the jack. I dissected and re-soldered it myself, but it was a shocking experience finding that out initially. And the battery compartment is awfully tight. I always have to grab some tool to pry out the battery when replacing it. Other than that, I've definitely gotten more than my money's worth of fun out of it! Hopefully it will last many years.