Evans BD22GB4 22" EQ4 Batter Bass Drumhead - ClearEVANS EQ4 Clear Bass Drumheads deliver a balanced sound, allowing for greater focus and tonal response. EQ4s feature a single ply of 10mil film and an internal overtone control ring designed for a controlled rumble and tight attack. Overall, this bass batter has a moderate attack, sustain, and brightness. EQ4 Clear drumheads also feature Level 360 Technology. Ply: 1 Technology (Treatment): Control Ring EVANS EQ4 Clear bass head is made with a single