Size1: 9mm hexagonal 3.0mm square hole. Size3: 10mm hexagonal 3.5mm square hole. Size2: 8mm hexagonal 3.1mm square hole. Fit for Universal Motorcycle Dirt Pit Bike with 8mm/9mm/10mm Connector. This is a combo item which inlcuded 3pcs Valve Screw Tool(10mm/8mm/9mm).
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