Why does this happen?

I was just messing around with my green laser when I discovered that if I pointed it at the pink plastic weight, the laser turned yellow. Here is the link to the video of me doing it:

https://www.youtube.com/watch?v=GvtJWLYF0cI


I quickly shined it at the TV to show that the laser is in fact green. I am just curious as to why this happens.