Socket can be driven with various tools including the Motion Pro® spark plug ratchet wrench, 3/8'' ratchet, 13/16'' wrench, tool kit bar, or a Phillips screwdriver placed through the 8.5 mm hole at the top of the socketOriginally designed for the Honda XR400R as a trail tool but fits many models with 18 mm plugsThin wall design to fit into low clearance plug cavity