It will be either : 11/16" ( 17.5mm ) or 41/64" ( 16.3mm ) FOR GENUINE WOLFRACE WHEELS. WILL SUIT MANY 6 STUD VEHICLES I.E. MITSUBISHI - TOYOTA - HONDA ETC WITH M12x1.5 THREAD WHEELSTUDS. Hexagon / wheelbrace / spanner / socket size is 21mm a/f.
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