The RAM Large Fish Finder Mount consists of a short double socket arm, 3.68" diameter round base, and 11" x 3" rectangle base. The round base includes a 2.25" D size rubber ball and contains pre-drilled holes, including the universal AMPS hole pattern. The rectangle base also includes a 2.25" D size rubber ball and contains a variety of pre-drilled holes that are compatible with several large marine electronic devices, including fishfinders and chartplottersFeatures RAM Mounts Ball and socket technology allows for near-infinite adjustability Made of powder coated, marine-grade aluminum Backed by a lifetime warranty