We bought an inverter at NAPA, don't know the brand or ratings off hand. We have it mounted in one of our fire trucks for running a TV/VCR that receives video from our thermal imager. This way the incident command can see first hand what's going on inside the structure as well as tape for viewing later. Also we can recharge portable radio batteries and extra imager battery on extended scene times. Has worked flawlessly. Don't know why cordless tool batteries would be different?