i have a jt distributing 6.8 barrel 20" with a2 flash hider and pic rail gas block. barrel is taper drilled for a2 front sight. complete bolt & carrier also. was a complete upper but i built a 223 hvy for prairie dogs out of it. have 2 17 rnd c products mags, they work great as ten rounders lol. 2 25 rnders too. some how they also work great as ten rounders. :roll: 20 rnds shot through it breaking it in per mike rock instructions. $360 for all these goodies shipped to you.