This Dual Flange Eartip is designed for Etymotic Research in-ear headphones. The construction foregoes the usual 3-flange design, which makes three points of contact within the ear canal, for a dual-flange one. The result is an eartip that is softer, more comfortable, and seals just as well as 3-flange designs. This package includes three pairs of eartips (six tips total), sized medium.