The MMSZ4685 from Micro Commercial Components is a Zener Diode with Zener Voltage 3.6 to 3.78 V, Zener Current 50 mA(zener test current), Voltage Forward 0.95 V, Current Reverse Leakage Current:- 7.5 uA, Power 500 mW. More details for MMSZ4685 can be seen below.