Mercury Floor Machines 1909 19 inch High Speed Harpoon Cushioned Pad DriverMercury Floor Machines 1909 Genuine Mercury 19 inch High Speed Harpoon Cushioned Pad Driver with Riser and 92 Clutch Plate Brush is 2" smaller to fit the machine, title is for machine brush fits. The High Speed Harpoon Cushioned Pad Driver has a double row, with Velcro style hooks that hold every type and thickness pad. This pad has the same features as the standard Harpoon Pad Driver but adds a . 50 inch thick foam between the driver blocok and the