Salt water chlorinators are usually installed during the pool building process but the Zodiac EI is the first salt water chlorinator specifically designed to be retro fitted. Drill a couple of holes with the drill bit provided in to any horizontal pipe longer than 6 inches and clamp the chlorinator on. Hang the power unit on the wall and connect up the wires. One more hole and a clamp for the flow switch and that is all that is required to start enjoying all the benefits of salt water chlorination.
The EI comes in 3 versions depending on the size of your pool.