I use them alot as I'm in a neighborhood. I make mine from 2 inch wide velcro cit 8 inches long. He can still crow some but its more of a aarrggh than a full on loud crow. You do have to take it off occasionally and re adjust it. Basically all your doing is blocking him from pushing air out fast enough to get that loud crow out. Mine eats, mates, and drinks fine. They will do a backwards dance when you put it on and stand with their head down until they figure it out. But it keeps him quiet and alive.Others here have had no luck using them some use them. I make mine tight enough to get a finger between it and his neck and adjust from there.
View attachment 2582942