The BB439 from Infineon Technologies is a Varactor Diode with Capacitance 43.0 pF (CT1), 34.5 pF(CT2), Capacitance Ratio 6.9 (2/25V), Forward Continous Currenrt 20.0 mA, Peak reverse voltage 28 V, Reverse Voltage 28 V. Tags: Surface Mount. More details for BB439 can be seen below.