The TCA-1 is a ceiling mount adaptor designed to attach ceiling mounts to a wide variety of trussing or pipe. Capable of adapting upto a maximum diameter of 3" or maximum cross section dimensions of 3" x 3" the TCA-1 will accomodate most common pipe and trussing cross sections. Designed to work with VMP's proprietary masts as well as industry standard 1.5" NPT pipe the TCA-1 is the perfect adaptor for your ceiling mount needs.