No crow collars

Does anyone know anything about no crow collars for roosters.... have you used them to they work?

My experience was that I was just slowly asphyxiating my poor rooster. At first is seemed to be working but then I realized he was having troubles eating properly. I would tighten it, loosen it, widen the strap, narrow the strap, but I came to the conclusion I was just slowly torturing my poor bird.

That's just my experience though...