Easy Provider 2.5mm Covert Listen Only Acoustic Clear Tube Earpiece 1 PIN for Ham Radio
These earpieces work ok, but seem to only last about a month, before they don't relay the sound from the radio to the ear anymore.  Probably cheaply made as I use it three times a week for eight hours per day.<br />I started using this ear piece on July 1st and it barely lasted until July 30th. 100 hrs total use time.  Looking for one that is more durable!