I actually did a little experimenting too. I made one collar out of ducttape, folded onto itself so it wasn't sticky. That one lasted an hour. I also cut the top part off a kid's sock (the stretchy part)... he's wore it 24 hours now. Haven't heard a single crow. I even put the baby monitor in the coop so I could grab him if he started crowing at 5am. Not a peep. I like the sock since he's white and the sock is white, can't even see it on him.
I received my collar in the mail today, but it didn't have the yellow tag (which I wanted as proof to the city "See, he's not a nuisance, he's got a no crow collar!") I emailed them about it, we'll see what they say. I actually quite like the sock
I might return the collar.
What they said. They do this weird neck expandy thing to get a nice loud crow out, can't do that with the collar.