SOP-MOD Upgraded Plumcrazy complete Lower Special Operations Peculiar Modification (Army) This lower is customized for the Skadi Upper. Our newest generation polymer lower is stronger and lighter than the average military spec aluminum lowers. This polymer lower is a billet design which means is more reinforced than any polymer lower on the market. Watch the video of 11,000 LBS Humvee running over 3 lowers and not one scratch!! The Plum Crazy Gen II lower receiver is a revolutionary polymer receiver able to withstand military standards. It offers an enlarged trigger guard. The triggers is a crisp and fast reset with no need of lubricating with NANO composite. The trigger breaks at average 4.5 lbs Just the SOP-MOD stock normally costs $100 separately.