DON"T BUY THIS!!!!!! I bought one already! It is a magnet glued together and cut into an arrow and hanging from a string. IT DOES NOT WORK!
Hubby talked me into buying it. Don't waste your money.
More superstitious wive's tales, or old farmers tales, rather. If you flip a coin, you have a 50/50 chance of being right and it won't cost you anything.
Even the ad sounds a little dodgy. At first he says you can sex them in 90 seconds but later down in the ad it says its only a 30 second investment of your time.