The Catphan® 504 phantom was distributed through Varian to assist in the commissioning and QA of the OBI kV imager on its Linac systems. The Catphan® 504 phantom consists of 4 modules that cover all required CBCT imaging tests for TG142. The Catphan® 504 phantom is no longer manufactured as of the fourth quarter of 2015. It has been replaced by the Catphan® 604 phantom.