Witchcatcher

The Witch Catcher is a necklace-like tool used by by folks to catch a witch due to certain spellwork applied on it. Any witch captured with this tool will eternally restrained. It also can be imbued with certain spell that can force the captured witch to obey the user and did the user's bidding.

It used by Dean and Crowley to capture Rowena and force her to perform a counter spell to send Lucifer back to his Cage.