ʻEkolu Rolling Millʻekolu mau ʻōwili e hiki ai i ka ʻōwili ʻana, ʻoi aku ka nui o ke anawaena o nā ʻōwili luna a me lalo, e kōkua ana i ka hoʻokele kaʻa, ʻoi aku ka liʻiliʻi o ke anawaena o ka ʻōwili waena, e ka ʻōwili o luna a me lalo friction drive.