The MSS40,PCR53-B47 from MACOM is a RF Schottky Diode with Peak Reverse Voltage 3 V min.@10 mA, Forward continuous Current 50 mA, Forward Voltage 0.35 to 0.45 V, Current 50 mA, Capacitance 0.15 to 0.25 pF. Tags: Surface Mount, N Type. More details for MSS40,PCR53-B47 can be seen below.