The BB857 from Infineon Technologies is a Varactor Diode with Capacitance 6.6 pF (CT1), Capacitance Ratio 12.7 (1/28V), Forward Continous Currenrt 20.0 mA, Peak reverse voltage 30 V, Reverse Voltage 30 V. Tags: Surface Mount. More details for BB857 can be seen below.