CFR › Title 21 › Part 886 › §886.163021 CFR §886.1630Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗Copy link(a)Identification. An AC-powered photostimulator is an AC-powered device intended to provide light stimulus which allows measurement of retinal or visual function by perceptual or electrical methods (e.g., stroboscope).(b)Classification. Class II.