In a track with a rotatable bushing which is brought into engagement with
a sprocket of a track-type vehicle, it is intended that strength is
enhanced rationally by link functionality sharing and by combination of
such assigned functional tasks for achieving further improvements in
rotatable bushing function. To this end, a track link comprises a
combination of an external link and an internal link; a coupler pin hole
is provided through the external link; a bushing hole is provided through
the internal link, and the thickness dimension of a bushing hole
formation part of the internal link is made greater than that of a
coupler pin formation part of the external link.