Evans Tri-Center Conga series simulates the bright, full sound and feel of animal skin while eliminating the problems associated with natural skin heads. This drumhead minimizes overtones and adds weight to the center to enhance the fundamental tone, featuring an extended collar that fits larger-sized counter hoops. EC1100, EC1175 and EC1250 are for LP™ Classic Models with “Comfort Curve” Hoop and Toca™ Professional Models with “Easy Play” hoops. EC0975, EC110E, EC1175E and EC1250E are for LP™ Gionvanni Models with “Extended Collar” Hoops.