This is a slider replacement kit includes (both left and right sliders) for various models of the Beyerdynamic headset. We offer a wide range of colors and finishes. This design is substantially more durable and stronger than the manufacturer's original component. Required T10 Torx Hex Key - Not included Screws not included - Uses existing screws Fits: DT 790 / DT 797 DT 770 / DT 770 PRO / DT 770 PRO HT DT 880 / DT 880 PRO / DT 880 PRO HT DT 990 / DT 990 PRO HS 200 Dyn / HS 200 Rotor / HS 200 Trend HS 400 MMX 300