Through an orthodontic re-treatment case report, this article explains the procedure of brackets positioning with the CLASS System, using the Set-Up Model Maker (SUM), and Occlusal Plane Reference (OPR). The self-ligating brackets and Smart Cap transfer tray system were used. The treatment was carried out with CLO Technique (Custom-made Lingual Orthodontics). Keywords: Lingual Orthodontics. Set-Up Model Maker. Occlusal Plane Reference. CLASS System.