OV-Watch is a clinically proven, patented fertility predictor that is cleared by the FDA. It is a wrist-mounted, bio-sensing medical device that tracks a woman's individual body chemistry to find the 4 crucial days before ovulation-her most fertile days of the month. OV-Watch has a special processor and biosensor that takes readings from your skin every 30 minutes while you sleep. This advanced technology works differently from other ovulation prediction devices in that it tracks chloride ion levels as opposed to LH or estrogen surges. It allows you to be able to fully utilize all 6 days of fertility- the four most crucial fertile days of a woman's cycle before ovulation and the time during ovulation. With OV-Watch, there are no messy, urine strips and no complicated charts. Just wear the watch at night while you sleep knowing that you will be alerted 4 days before ovulation, giving you plenty of time to plan mutiple romantic interludes if desired. If women use a LH urine kit that only detects hours before ovulation, they may miss their most fertile time since by the time ovulation occurs, the egg, which only has a life span of approximately 12-17 hours, is already beginning to die. Sandra Ann Carson, President of the American Society for Reproductive Medicine states, "Although LH peaks accurately detect ovulation, they do not identify the pre-ovulatory fertile period. Up to two thirds of pregnancies are conceived at or prior to ovulation." Nothing can provide you with your entire fertility window like OV-Watch. The Starter Kit comes with the OV-Watch wrist computer, English language Reference Manual and Quick Start Guide, Plastic storage case and 1-3-month supply of sensors. One sensor will last one full cycle. OV-Watch has a 30 day money back guarantee (any reason) and a full 6 month warranty. OV-Watch is there for its customers. OV-Watch's Customer Care line is 1.866.OVWATCH for service or free medical education through our customer newsletter.