CFR › Title 21 › Part 882 › §882.591021 CFR §882.5910Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗Copy link(a)Identification. A dura substitute is a sheet or material that is used to repair the dura mater (the membrane surrounding the brain).(b)Classification. Class II (performance standards).