The RAM® Tough-Mag™ 48MM 3-Point Magnetic Mounting Base (RAM-MAG48-3U) consists of an aluminum plate with three magnetic ends and three 48mm external magnets for mounting any flat glass surface, like windows. The plate contains pre-drilled 4-hole AMPS pattern for attaching a recommended C size drill-down ball base. The base is designed with rubber coated magnets to prevent scratching the mounting surface and reduce the impact of the jarring magnetic pull. Each external magnet includes a handle in order to easily install the base to a window. Compatible with any sturdy, flat surface up to 6mm in thickness.