The DL85C20 from Micro Commercial Components is a Zener Diode with Zener Voltage 18.8 to 21.2 V, Zener Current 0.5 mA, Voltage Forward 1.0 V, Current 10 mA, Current Reverse Reverse Leakage Current:- <0.5 uA. More details for DL85C20 can be seen below.