I have used the ovulation test a couple of times and both times the tester only works 4 times and then it breaks. I use it as directed and follow the instructions. You need to ensure the quality of your product because these tests are not cheap and many women can't afford to spend another 50 dollars because the tester stops working. Also, make it so you can just buy the strips so it doesn't cost as much. Don't take advantage of women.