The Silverbolt MIS Mainframe HA Screw System has not been evaluated for safety and compatibility in the MR environment. The Silverbolt MIS/Mainframe Spinal Screw Systems has not been tested for heating, migration, or image artifact in the MR environment. The safety of the Silverbolt MIS Mainframe HA Screw System in the MR environment is unknown. Scanning a patient who has this device may result in patient injury.