Aspects describe an earpiece with structure for positioning and retaining the earpiece and with structure for sealing against the entrance to the ear canal. According to aspects, the retaining structure has at least one substantially elliptical leg configured to follow the curve of the anti-helix and/or the cymba concha at the rear of the concha. The leg increases in thickness from a tip of the earpiece towards the body of the earpiece. The sealing structure is substantially frusto-conical and extends from a nozzle. The nozzle is angled to align with ear geometry. In an example, he sealing structure has a slight radius on an outer surface of the sealing structure. In another example, the sealing structure has a substantially constant thickness from the nozzle to the wide end of the sealing structure.