Devices commonly classified here include electromyographs (EMG), electroencephalographs (EEG), evoked potential systems, nerve conduction velocity analyzers, spirometers with electronic output, and multi-parameter patient monitors that do not fall under more specific headings. The key criterion is that the apparatus measures or records physiological electrical signals or parameters for diagnostic purposes and is not covered by a more specific SITC code such as electrocardiographs (77411).

Each device type has its own FDA product code and regulatory class. Importers must file an FDA Prior Notice or entry affirmation through the Automated Commercial Environment (ACE), identifying the device's 510(k) clearance or PMA approval number. FDA may detain shipments for examination if the device lacks clearance documentation or if the foreign manufacturer is not registered. Consulting a licensed customs broker with medical device experience is advisable given the variability across device types in this heading.