The one Dave speaks of is an earlier model--before Kostiner realized the need for outlet tubes, rather than just letting it flow over the end. There should be three plexiglass outlet tubes that you would attach soft tubing to: the inlet (on the white block that runs the length of the front of the washer), the tube on the overflow chamber, and a tube at the back of the washer on the left side (facing it from the front) that has a clamp for adjusting the amount of aeration. This tube is also closed off when the washer isn't in use to keep it from draining out. I believe all three have a 1/2" inner diameter, but the inlet tube is thick-walled--not necessary on the other two.
(Actually the inner diameter is 5/8".)