Evans clear Genera Resonant drum heads produce a full, round sustain with strong upper-mids that increase projection without sacrificing sustain. They are ideal for enhancing tone when combined with a 2-ply batter head. Evans Level 360 technology is incorporated to extend the level playing surface of the drumhead, 360 degrees around the drum. The vertically enhanced collar design guarantees even contact with the critical bearing edge of the drum shell, resulting in: ease of tuning, extended pitch range and optimum quality of sound. Evans Level 360 technology resolves the age-old dilemma of traditional synthetic heads consistently not fitting the drum shell without using considerable force.