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Is this an f marked front sight block? — 2 Answers

by Rawdog11, from MN, United States Asked on September 11, 2022

Name Luth-AR 5.56mm 11.5in Lighweight Barrel w/FSB (3.3)
$194.99 $183.29 Save $11.70
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Answered by Ethan, Gear Expert, from IL, United States, on September 14, 2022

Yes. The Luth-AR 5.56mm 11.5in Lightweight Barrel is a Government profile barrel with an F marked FSB. It will not include the front sight post, spring and detent.

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Manufacturer Answer
A
Answered by Luth-AR, Manufacturer from MN, United States, on September 14, 2022

The 11.5" barrel will have an F marked front sight base that is 1.98" tall or .04" taller than non F marked front sight basses.

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Last updated 2026-02-01 UTC.