Zener diodes are usually defined as wattage required. These are a range of 500mW voltages that will be suitable to use if you project requires any of the following pre-fixes:-
The common ones:-  BZY88c, BZX55c,
The not so common ones:- BZX46, BZX60, BZX75, BZX78, BZX79, BZX83, BZX84, BZX85, BZX87, BZX-88, BZX96,
BZX97, BZY83, BZY85.
All will be suitable for use with our Z4 Range. ie if your project calls for a BZY88c10v the select a 10v option from the dropdown menu as Z4+ Voltage in the case of BZY88c10v the order Z4-10v. The same analysis goes for all pre-fixes above.