Deal: Get 4 months of free Google Play Music and YouTube Red service

So, for a limited time, Google offers four months of free YouTube Red and Google Play Music service. However, there are some limitations that will probably not be to your liking. First off, you can take the deal if you're already a subscriber of either of the two services.
Keep in mind that if you've previously redeemed a two months Google Play Music deal before, you might be eligible for this one that offers four months of free service since they are different deals. The same goes for the YouTube Red service deal, apparently.
source: AndroidAuthority