The Cross Machine Tool Ultra Precision Upper Receiver Part# UPUR-3A Right Side Charged Upper  is the perfect Mate to your UHP-15 lower receiver or would also be a great match with any Mil-Spec lower. The UPUR-3A is machined from Billet 7075 T6 Aluminum unlike the more commonly used 6061. Using the 7075 T6 aluminum gives the UPUR-3A a 65% increase in strength & rigidity over 6061 aluminum receivers. The UPUR-3A is machined on a 5 Axis machining Center to reduce the number of operations/setups required to complete. This machining process allows the highest possible accuracy to be obtained over the traditional 3 or 4 Axis machining method. The UPUR-3A is designed for increased function, performance & to provide an advanced modern appearance & feel to the AR15 platform weapon system. The UPUR-3A is a Precision upper great for a Precision long range rifle build or for a more minimalistic build approach.Features:     5 axis machined from 7075 T6 billet     Engraved “T” numbers     1913 picatinny Rail flat top     Mil Spec Type III class II hard coat anodized Black     Increased wall thickness for added rigidity     Compatible with Mil spec parts     Compatible with most aftermarket handguard/rail systems     Precision Carrier bore diameter to aid long range accuracy performance     Ejection Port sized for compatibility with 458 SOCOM rifle builds with no additional machining required on ejection port     Weighs 7.7 ozs     Lifetime warranty against manufacture defects     Compatible with "Tactical Link" Enhanced Battery Assist Lever     NO forward assist, Shell deflector & dust cover     Designed for use with Young MFG National Match right side charged BCG (Not Included)     Can also be used with traditional Mil-spec charging handle     M4 feed ramps Specifically designed to work with Young Manufacturing side charging carriers and may not work with other manufacturer's carriers.