Evans Coated G1 drumheads feature a single ply of 10mil film that blends bright tone, sustain, sensitivity, and durability. The G1 drumhead produces an open and expressive sound and contains a coating that delivers additional warmth, focus, and depth. Tuned low, it produces a cavernous rumble that emphasizes the natural sound of the shell.https://www.oosthavens.co.za/product-category/drums-percussion/vellums/