I have lots of Athenas already, as it's a staple in my bag. I love UV color changing discs, so when I saw the Athena releasing one I was all over it. Unfortunately, I was a little disappointed to see that the color change in direct sunlight is almost unnoticeable. It changes from white to about a 2% pink. This hasn't been my experience with other UV discs in the past, which is why I was dissapointed when I saw this one. Great disc! Not so great UV change. Worth noting tho, maybe mine was a one-off fluke?