Rainier Arms UltraMatch Billet Upper and Lower Combo Set MOD 3  Our billet sets are CNC machined from solid billet 7075-T6 aluminum which is 70% stronger than the commonly used 6061 aluminum and finished with milspec hardcoat anodize to a surface hardness of 60 Rockwell. We have designed our lowers with an ambidextrous magazine release and bolt release with extended latch for smoother deployment. The precision machining on our billets are well known in the industry and we are excited to introduce our combo sets for your next rifle build. Features: Ambidextrous Extended Bolt Release Ambidextrous Magazine Release M4 Feed Ramps 7075 Billet Aluminum Flared Magwell Integrated Trigger Guard QD Socket machined in Tensioning Screw for proper Upper/Lower Fit FFL Required Before Shipping. Please have your dealer email their license to [email protected] or they can also fax it in. Please give us a few days to process the information.