Center rigger base mounts are constructed from 316 marine grade stainless steel. Installation is simplified by the use of a clamp-on mount, that fits either 3/4" IPS or 1" IPS pipe found on the hoop of most standard T-Tops. Designed for universal use with TACO center riggers and other brands. Accommodates 12' 1-1/8" center rigger poles, which telescope to less than 5' 6".