I'm on my second try of this product. Amazon's great customer services change the other because 5 or 6 keys was wrong, my numerical pad doen't works, when I press 7 1 6 9 or 3, the keyboards sends tons of diferent orders, even to send my computer to stanBy.The second keyboard was best, but it still have to many bugs, my left hand CTRL, SHIFT, and ALT keys doesn't respond sometimes, and others respond but doesn't hold the signal to make multiple selections.Final words... Try later when the bugs are corrected. now try another manufacturer