POWERBUILT Valve Adjustment Tool.
This tool makes adjusting valves easier on engines with a 10 mm jam nut and slotted valve adjusting stud. First, it’s designed with a view window to see the screwdriver blade position and engage it with the valve stud more easily. Then the unique all-in-one design positively tightens the jam nut while preventing stud rotation. Fits Honda B/D/H/K-series engines.