How the ---- can I tell what year some injectors are from?

The person I sold my old hatch to running with 450 blue tops and an AFC did not want them. So he wants to trade me for stock injectors. I told him I had a set, but now I'm not sure if these are from the old 90 si or if they are from a 95 b16a.......

The only markings I see on the shaft of the injector is EF 22.
on the black top it sayd japan "KEI HIN" and on the other side there's a 4 followed by 3 asian characters.

If the EF 22 means it's from an EF then I'm good to go. Just need to know. Worst thing, he puts them in and the car won't start, I guess......

Thanks for your help

 

Test the resistance of the injector...low impedance is obd0, high impedance is obd1. You want the low impedance one's to go back in in conjunction with the resistor box.