this sc-15 was custom built has a mur-1 vltor billet upper-spikes lower-white oak super match heavy conture barrelcryo hardened & teflon lined-enhanced smith ind carrier yhm back up iron sights-gisselle ssa trigger group-smith vortex flash hider- kns anti rotation pins- magpul ctr stock/naid grip- yhm free float quad rail- heavy buffer and wolf spring