Namura Top End Rebuild Kit for 1994 21 Kawasaki KAF620 Mule models 77.50mm NA 20062 6K 1996 Honda CBR900RR Fireblade 2018 Polaris 800 Pro RMK 2018 Polaris 800 Pro RMK Product Details Product Line Renthal Twinring Sprocket Part Number 1540 520 48GPSI Fitment Type Model Size Specific Fitment Use Type Unit Sale Qty Each Style Ultralight Grooved Size 520 Chain x 48 Teeth Position Rear Material 7075 T 6 Aluminum Alloy Color Silver Finish Sprocket Teeth # 50mm Age Group Gender Position Tire Diameter Speed Rating Load Rating Wall Construction Tire Tube Type Rim Size Material Color Finish Functional Length Cable Sleeve Length Cable Sleeve Travel Driver Seat Length Passenger Seat Length Driver Seat Width Passenger Seat Width Overall Seat Width Overall Seat Length Piston Cylinder Size 77 Namura gives you a higher performance piston without the higher price