Element Case CFX for Apple iPhone 8 Plus and 7 Plus - Black MERC 3 (Material Engineered Reinforced Chassis) Engineered composite materials reinforce a polycarbonate sub-frame to create a chassis that resists twisting and bending. Carbon Fiber Reinforced - Aerospace grade carbon &#xFB01;ber used in MERC 3 reinforced chassis design. HIT (High Impact TPU) Crowns - Co-molded elastomeric TPU crown design provides extreme impact protection. Mil-Spec Approved - CFX meets military speci&#xFB01;cation drop-test requirements. Rapid Fire Buttons - Integrated buttons protect iPhone 7 Plus controls while providing quick and easy use of volume and on/off functions.