The V-12 Series from Valken Tactical including the V-12 Ultra SOPMOD is available to order at their online store/// "The V-12 ULTRA SOPMOD is a base M4A1 configuration for the SOPMOD (Special Operations Peculiar MODification) kit is an accessory system. The V-12 ULTRA Series the ultimate in durability and versatility, with it's reinforced Aluminum Alloy Body and rock solid buffer tube mounting system that was designed with the hardcore player in mind.