AVAILABLE NOW! Introducing the all new Grand Slam 850 Electric VHF Antenna Mount! Designed with safety and innovation in mind, boaters can adjust the position of their VHF antenna with the simple push of a button from the comfort of their helm. The GS-850 is a fully electric unit with hidden wires inside the hardtop. This mount easily installs to the surface of the hardtop and fits all top thicknesses.