Universal Precision Yellow Probe TubesProbe tubes are designed for use when performing real ear measurements (REM). Yellow probe tubes are universally compatible with Siemens, Madsen, MedRx, Interacoustics, Inventis, Frye, and Audioscan. Note: The package of 36 has been discontinued, available while supplies last. Features Disposable, single use probe tubes 76mm (3") length with beveled tip Includes marker ring on each tube for marking ear canal depth MPN: U76MBY Made in USA Available in