FSB, not F marked

[Tim]

This FSB needs a sight pin, spring, and detent. It’s not “F” marked. Think that makes a difference for replacing these parts?

Aero Precision AR15 Front Sight Post Kit

Mil-spec AR15 front sight post kit is intended for use in AR15's that have a front sight base (FSB). These parts would be perfect for your new build or as emergency spares.

ar15discounts.com

 

[Exspiravit]

No. I have a non F on a barrel I bought., KNS front sight dropped right in.

 

[Chuckman]

Assuming it is Mil-Spec the pins should fit. Only difference between f and non-f are shelf fight which requires a change in zeroing iron sights. The rest should be the same.

 

[USMC6094]

0.040 inch height difference, only time it comes into play is zeroing to a fixed carry handle, or on a shorter barrel. But its nothing a little quality time with a file, a caliper, and some cold blue won't remedy.