Evans G1 Coated drumheads feature a single ply of 10mil film that
  blends bright tone, sustain, sensitivity, and durability. This
  drumhead incorporates Evans Level 360 Technology for ease of
  tuning, extended pitch range, and optimum quality of sound, and
  produces an open and expressive sound featuring a coating that
  delivers additional warmth, focus, and depth. Tuned low, it
  produces a cavernous rumble that emphasizes the natural sound of
  the shell.