The Auxx-Lift is usually mounted on any ceiling (rafters/joists/sloped ceiling) THIS KIT IS OPTIONAL: Usually the lift's motors run parallel to your ceiling joists. If you need the motors to operate perpendicular for your joists you will need this kit. This extra package will transform the platform 90 Levels It https://auxx-lift-products87530.wiki-racconti.com/8229147/not_known_factual_statements_about_auxx_lift