The Carbiepoles™ Enhanced Vertical Mounting System is a unique mounting base for boats. This hardware set is perfect for applications where you want to temporarily mount a sun shade pole to a solid surface. The vertical base is compatible with 38mm/1.5" Carbiepoles™ Adjustable Shade Poles. This mounting system is comprised of two parts: a flush mount base, which is permanently installed on the boat, and a vertical enhanced socket that threads in with a Higbee thread. When the socket is removed, a stainless steel plug is threaded in to provide a finished appearance.