Actually, it's a collar that Thor so convincingly acted like was strangling him half to death that I was afraid to put it on Loki. So I used it as a hat.
Then Loki decided it would make a fine toy.
A tossing toy.
Then Thor had to get in on the hat tossing action.
The "hat" is now in hiding, a human supervised toy only because I'm afraid Thor will chew off and swallow one of the bells.