It's a Chris Mackey masterpiece called Pan & the Cache Guardians. It's incredible 3D relief on the front, with the little winged cache guardians on the back.
Let's hope they give some extra protection to your cache.....
With this coin comes a pathtag, with a unique number, which can be logged at pathtags.com
Size: 44 mm, 4,5 mm thick
Trackable at Geocaching.com with its own icon.