I have one of those around here someplace. They're okay, but I prefer a 1xAAA or 1xAA light for EDC. Now that my last clock still running AA primaries died to a alkaline battery failure, everything has been switched over to NiMH, except for a couple lights that run on 18650 Li-ion. I don't have any need for 9 volt batteries, even my smoke detector runs on AA's.