Plantronics 78333-01 Headset Cable Left Connectors: 1 x sub-mini phone 2.5 mm - male Right Connectors: 1 x RJ-9 - male Designed For: Panasonic KX-T208, T2375, T3800, T3815, T3821, T3823, T3824, T3825, T3830, T3831, T3832, T3835, T3842, T3845, T3880, T3900, T3920, T4000, T7425, T7433, T7436, T7520, T7531, T7533, T7536, T7550, T7625, T7630, T7633, T7636, T7665, T7667, T7668