Persona Fertility Monitor, previous model, £80 approx if new. Use for contraception or when trying to conceive. Needs AAA batteries and test sticks. Test sticks available from Amazon, approx £13 for 8 which is a months worth. Instructions included. You set the monitor to start on the first day of your cycle, wee on a stick, put it in the monitor and it goes red if you are fertile, green if you aren't. Also tells you when you will ovulate. Found it really useful but no longer need it. Free to anyone who would benefit, I only want payment for the postage. Let me know if you need more info!