The Food and Drug Administration (FDA) is classifying quality control material for cystic fibrosis nucleic acid assays into class II (special controls). The special control that will apply to the device is the guidance document entitled "Class II Special Controls Guidance Document: Quality Control Material for Cystic Fibrosis Nucleic Acid Assays." The agency is classifying the device into class II (special controls) in order to provide a reasonable assurance of safety and effectiveness of the device. Elsewhere in this issue of the Federal Register, FDA is announcing the availability of the guidance document that will serve as the special control for this device.