The AL7001CR (1-3/8ID) is the solution for boats with a tower or when a lower angle is desired. It has a slightly larger footprint (4x 7). Ruggedly constructed from marine grade anodized aluminum. It can be easily attached above or below the standing platform or any flat surface. It comes in a standard angle of 22 degrees that gives it a low rise. Anodized in Bright Silver it is as strong as it is attractive. It accepts all the same poles as the AL7000 series holders.