The Evans E-ring is an easy-to-use external overtone control ring which "floats" on the surface of a drumhead. It rounds out and flattens the drumhead's sound and allows for easier tuning as well as emphasized attack and low-end. They are available in three different assortment packs designed to accommodate most drumset configurations. The Standard Pack includes 12", 13", 14", and 16" E-Rings.