Evans HD (Heavy Duty) snare drumheads effectively balance durability and sonic response. HD heads are made with a coated outer ply of 5mil film and an inner ply of 7.5mil film, plus a 2mil control ring on the underside of the head, damping excessive overtones just enough to balance your sound. Evans HD heads have a slightly more defined attack, short sustain, and moderately bright tone, plus the added durability of Evans premium coating. This coated head also features Level 360 Technology.