Large Mowers use 2 Free Spinning, Counter Clockwise Blades for each Spindle. Center Hole to Blade Tip Length 11-1/2.90 Rear Mounted 3 Point Finish Mowers. Set of 6 blades for woods rm90 rm990 p990 90 grooming finish mower # 24590kt six (6) new aftermarket replacement blades made for woods mower models rm90, rm990, p990.