It is a freezer-weight plastic storage bag filled with raisins and peanuts. I toss a bag, sealed, into the pen in the morning. They all pounce on it because they recognize the raisins and peanuts inside and they claw and they scratch at the bag until, several hours later, they succeed in making a tear in the bag.
Sometimes the tear is only large enough to permit them to extract a singe raisin at a time, and sometimes they bust it wide open and take all the contents at once. But as a rule, the bag lasts long enough to provide hours of entertainment from the top of the pecking order, until hours later, the lowest ranked are working on the bag, often with just one raisin left in it.
It's cheap, simple, and keeps the troops occupied on those days when weather confines them to their pen. It sure beats them pecking on each other!
