IT IS NOT A SHOCK COLLAR. The No-Crow Rooster Collar is made from mesh and Velcro, and fully adjusts to fit the rooster perfectly. They are worn with a pinky finger's width of space between the collar and your rooster's neck. The collar prevents roosters expelling the contents of their air sacs all at once, preventing them from unleashing a full-powered crow. While wearing the collar, they can still vocalize in all their normal ways--but the volume is limited. The collar is made to bend and flex with the rooster's neck so he can do everything he always does (eat, drink, dust bath, other vocalizations). It isn't tight enough to bother them, and it allows their necks total freedom and flexibility to expand.
I know what you mean, I like to be a good neighbor. I have a friend who's neighbor constantly hassles him about one coturnix rooster crowing a few times a day. The same complainer has an ill mannered dog who constantly barks and growls at anyone who passes their common fence or any commotion in my friends yard.