Question About AR-15 A2 Front Sight Posts...

[MRE Milkshake]

So when it comes to A2 Front Sight posts while having a flat top receiver, do I need to get a F marked A2 front sight post, or a non marked one for just general use with backup iron sights?

(PS, I have my reasons for wanting the A Frame over flip ups)

 

[BIGE7.62]

F marked .
You can use the other one but you have to use a different front sight post . I don't remember the height or specs anymore

 

[MRE Milkshake]

F marked .
You can use the other one but you have to use a different front sight post . I don't remember the height or specs anymore

Okay noted. I'll be sure to get the f marked one then. Thank you!