AR bolt design

AR/M4 AR Technical Discussion
1

I came across this bolt the other day and I have no clue who makes it. The only markings on the bolt itself is E092 that is under the extractor. I have never seen one with the that metal piece in it. When I pulled the extractor off, there is two red springs. Any able to shed light on this for me? Thanks

2

E3 Enhanced Bolt from Knight’s Armament

http://www.knightarmco.com/weapon-features/?features_con=e3_bolt&feature=multilug_impoved

3

Only to be used in a KAC E3 barrel extension.

4

If you want to get rid of it, I’ll buy it from you!

5

Thanks for the replies, and for the pm’s with the info.