The ML4610 from Spectrum Control is a RF PIN Diode with Forward Current 10 to 40 mA, Reverse Current 10 uA, Breakdown Voltage 15 to 25 V, Thermal Resistance 70 to 80 Degree C/W, Forward Resistance 1.2 to 1.5 Ohms. Tags: Surface Mount. More details for ML4610 can be seen below.