The ELD rule effective February 16, 2016, established minimum performance and design standards for hours-of-service (HOS) ELDs; requirements for the mandatory use of these devices by drivers currently required to prepare HOS records of duty status (RODS); requirements concerning HOS supporting documents; and measures to address concerns about harassment resulting from the mandatory use of ELDs (80 FR 78292). Many lessons have been learned by FMCSA staff, State enforcement personnel, ELD vendors, and industry in the intervening years. These lessons can be used to streamline and improve the clarity of the regulatory text and ELD specifications and answer recurring questions. Additionally, there are technical modifications responsive to concerns raised by affected parties that could improve the usability of ELDs. FMCSA is seeking information to determine what changes would be warranted.