These convenient bands wrap around the twist of your decorating bag, then lock to prevent icing from oozing out of the top. As you squeeze out icing, slide the tie down to maintain the pressure. The Wilton Icing Bag Ties Set contains 12 Icing-Bag Ties. Convenient bands wrap around the twist of your decorating bag, then lock to prevent icing from oozing out of the top. As you squeeze out icing, slide the tie down to maintain the pressure.