Explorer's Choker: Where is it?

I can't seem to find any data telling where this item is actually obtained and how to obtain it. Can anyone answer?

Is either AV or CC not sure which one

Drops in CC, chest before Chimera I believe.

Thank you very much for the swift responses.

Mooglebox comments say AV and CC

http://mooglebox.com/entries/explorer's-choker.php