Evans red Hydraulic series include a thin film of oil between two plies of 7mil film offering amazing durability, and a deep low end and short sound. This technology has been around for a long time in early 70's rock and roll. Hydraulics are famously easy to tune, making them a perfect fix for troublesome drums and players with little tuning experience. 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. Beyond all this features the red head is a beautiful head that makes your drums outstand. If you are looking for red heads, Evans Hydraulic are your best choice.