Towing tubes/skiers

use the harness that attaches to the eyes on your transom as mentioned by Tsubaki and and a ski rope or tubing rope (usually shorter). West Marine sells them.


http://www.westmarine.com/webapp/wcs...0&classNum=391

There are a lot of different ones and different length lines depending on what you are doing. Water skiing, tubing, wake boarding,knee boards....