Section 868.1910 - Esophageal stethoscope(a)Identification. An esophageal stethoscope is a nonpowered device that is inserted into a patient's esophagus to enable the user to listen to heart and breath sounds.(b)Classification. Class I (general controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to § 868.9 .47 FR 31142, July 16, 1982, as amended at 65 FR 2313 , Jan. 14, 2000