Spaquip variable colour LED light - Can only be used with Spa-Quip controllers - Spa Power 400, 600, 800, 1200 series -Lamp comes complete with Spaquip Q3701 Light Housing - Suits 63mm hole size. Lamp can be used with other light housings from Waterway or O'Ryan, etc, however may need to be glued to the rear light reflector/globe holder. This enables a Spaquip LED light to be retrofitted to a spa along with a new Spaquip Spa Power controller when upgrading from an earlier system of any brand with a light housing of unknown make.