Various implementations include an eartip for an earphone earpiece. The eartip can be configured to reliably fit a plurality of ear shapes. The eartip can have a body and a sealing structure defined by a set of dimensions that are configured to seal the ear canal of one or more users. In certain implementations, a notch in the body permits flexion of the body during coupling or decoupling of the body from the mount and provides sufficient hoop stress around the mount to retain the eartip on the mount during use of the earphone earpiece.