The owner slots a cartridge into the band around 6 p.m. before they are planning to go out. The cartridge is disposable, which will cost a few dollars. The analogy is, you put a raw piece of meat on the counter, over a few hours it turns brown. Similarly you open a cartridge, it oxidizes. It goes beyond step counting, it goes beyond heart rate, it’s reading bio-analytic through your skin. The skin ends up being a superhighway of molecules. While users can detect their BAC (Blood Alcohol Content) for now, the technology translates into detecting other things like caffeine as well - The possibilities are numerous.