Herco Spitballs are great for cleaning brass instruments between baths. There are 15-18 treated foam cleaning spitballs per jar. Removes dirt other cleaners have left behind. The standard size was designed for trumpets, cornets, french horns, and small bore trombones and contains 18 spitballs. The large size is for large bore tenor trombones, bass trombones, and baritone horns and contains 15 spitballs.