2X-S Custom-Fit EarphonesSound Signature: studio reference, full range response Drivers: 2 balanced armatures: 1 high, 1 low with single crossover Our classic custom in ear monitors designed for clear, accurate, studio reference response. 2X S has the same sound signature and drivers as our 2MAX, with the inherent safety of slightly lower sensitivity. Its flexible, soft silicone earpieces ensure long wearing comfort and perfect fit with maximum isolation and secure seal.