No drilling into your spa cabinet needed. Under-spa plates are held securely in place by the weight of the spa. Requires as little as 18" of clearance. When folded down, the cover stores neatly on the side of spa to provide a full view. Zinc-plated and powder coated finish. Fits most spas up to 96". Easy to install Please note: These cover lifters are not designed to hold the weight of a water logged/heavy cover and will bend if used with them.