Premium Undermount Hot Tub Cover Lifter. The Cover Caddy gas spring assisted cover lift defines versatility and effortless spa cover removal. Its unique design allows for installation on an array of spa shapes and sizes including round, octagonal, and spas with large radius or cut corners. The Caddy’s new under-mount base plate provides for a complete installation within minutes. The addition of a powerful gas spring makes lifting and lowering your spa cover easier than you ever imagined. Equipped with an industry leading 5 year warranty.