What is this thing called?

What is this thing called?
I think it's a musical instrument of some sort, but I've never seen one before.
It's sorta' like a tambourine, but with metal rings that make noise.
About 18" in diameter, with see-through plastic on one side,
and one padded area on the perimeter that is for holding it (I think).
I literally found it in the street, in it's convenient carrying case.
?
https://www.dropbox.com/s/q2gtab3k1m64svy/IMG_20160821_164419_953%206.jpg
https://www.dropbox.com/s/8wni5l1o34dbxu1/IMG_20160821_164510_909%206.jpg
Thanks.
Mark53
I think it's a musical instrument of some sort, but I've never seen one before.
It's sorta' like a tambourine, but with metal rings that make noise.
About 18" in diameter, with see-through plastic on one side,
and one padded area on the perimeter that is for holding it (I think).
I literally found it in the street, in it's convenient carrying case.
?
https://www.dropbox.com/s/q2gtab3k1m64svy/IMG_20160821_164419_953%206.jpg
https://www.dropbox.com/s/8wni5l1o34dbxu1/IMG_20160821_164510_909%206.jpg
Thanks.
Mark53