ECB84, is a popular D'Addario hybrid custom light Flatwound set combining the high strings from an ECB80 (.40 and .060) and the low strings from an ECB81 (.80 and .100). This set is optimal for players looking for a more comfortable playing tension in their flatwound sets while still maintaining a rich low bottom end . Fits long scale basses with a string scale length of up to 36 1/4 inches. D'Addario XL Chromes are the industry standard in flatwound guitar strings. They deliver a round, full low end without losing punch, making them ideal for jazz players of all types. Wound with flattened stainless steel ribbon wire, then polished to unparalleled smoothness, it's no wonder that XL Chromes are the world's most popular flatwound strings. Gauges: .040, .060, .080, .100.