The CFX features MERC 3™ technology, combining genuine aerospace grade carbon fiber with rigid polycarbonate to create a reinforced chassis that resists twisting and bending. The reinforced chassis is co-molded to top and bottom crowns comprised of unique elastomeric TPU which provides superior impact protection. MERC 3™(Material Engineered Reinforced Chassis) Engineered composite and alloy materials reinforce a polycarbonate sub-frame to create a chassis that is rigid, light to resist twisting and bending. Carbon Fiber Reinforced. Areospace grade carbon fiber used in MERC 3™ reinforced chassis design. Hit™ Technology Co-molded Hit™ (High Impact TPU) technology provides extreme protection at both ends Fast Tap™ Buttons Integrated buttons protect iPhone controls while providing quick and easy use of volume and on/off functions.