So im not too familiar with injector lingo but I just need a bit of guidance and info that i couldn't find too easily.

Got a fuel rail with injectors for a relatively good deal so i assumed there would be issues.

First i compared the injectors. All say python up top and a number/letter under the JECS in the middle. Question number one, B-4-L-0 were the numbers or letters under the JECS...should they all be different or the same.. Question number two, I noticed B injector was missing the smaller o-ring, is this an issue, or are these easily acquired? Question number three is, the lower portion of injector 0 has brown plastic, while the other three match black, issue, or normal? All in question is pictured below. Thanks in advance.



Injector B



Injector 0




Sending off to be tested asap.