LycoGear Heavy Duty Dual Industrial Modular Magnetic Base Mount for Strong Magnets – Super Strong Professional Dual Magnet Mount Supports Vertical Holding Devices up to 20 lbs. The two magnetic bases are 78mm in diameter and have 6 industrial strength magnets on each base. It is compatible with any 1-inch ball mounting solution. Our heavy duty double circular magnetic base that attaches to flat metal surfaces including forklifts, metal cabinets and shelving, and other warehouse locations. Attached to the base is a 25mm ball adapter that can be used to mount components compatible with 25mm balls (not included). The heavy-duty magnetic base is perfect for use on surfaces where drilling or clamping is not ideal.