The clear Sennheiser IE PRO Mono is a one-sided mono cable that connects to either the left or right earpiece of an IE 100 PRO, IE 400 PRO, or IE 500 PRO in-ear monitoring headphone. It is designed for in-ear talkback, providing discreet one-sided listening for a news anchor or host.

On one end, the 5' cable is terminated with a 3.5mm TS mono connector that plugs into any mobile or audio device with a 3.5mm jack. On the other end, a proprietary connector securely connects to the earphone. The cable sums incoming stereo signals into a mono signal heard in one ear. The rugged twisted-pair design increases resistance to structure-borne noise for a cleaner sound at all volumes.