The MMSZ4690 from Micro Commercial Components is a Zener Diode with Zener Voltage 5.6 to 5.88 V, Zener Current 50 mA(zener test current), Voltage Forward 0.95 V, Current Reverse Leakage Current:- 10 uA, Power 500 mW. More details for MMSZ4690 can be seen below.