Manufacturers Part Numbers: 453--520-13GP|112U-520-50GEGN|C416. Renthal Sprockets & Chain Kit - Front & Rear Ultralight Sprockets & R3 O-Ring Chain. THIS CHAIN & SPROCKET KIT INCLUDES:. Sprocket-Front: Tooth. Sprocket-Rear: Tooth - Green. CHAIN: Renthal R3 O-Ring Chain - 520X120 Links. FRONT COUNTERSHAFT SPROCKET. Standard front chainwheels are long lasting, hard wearing entry level front chainwheel.. Constructed out a specially developed Nickel-Chrome-Molybdenum steel which is case hardened and core refined to give the ultimate combination of strength and hardness.. ULTRALIGHT REAR SPROCKET. Renthal Ultralight rear chainwheels are manufactured to extremely tight tolerances from a special material developed to withstand the rigours of supercross, motocross and enduro racing.. The 7075 T6 aluminum alloy rear chainwheels are 66% lighter than steel, yet incredibly durable. Their advanced tooth profile, concentricity and accuracy of fit provide maximum power transfer and long-life.. R3-3 - MX SRS O-RING CHAIN. A premium high strength sealed ring chain with excellent impact load resistance designed specifically to withstand the stress found in offroad applications where an o-ring chain is desired. The R3.3 chain has been upgraded to the R4 ranges' proven quad riveting manufacturing process. The Rivet link has also been changed to a hollow end to facilitate easier installation. Nitrile Self Regulating Seals (SRSTM) retain a special vacuum injected grease around the critical pin and bush area, which extends the life of the chain.. Average Tensile Strength: 7420 lbs.. Number of Links: 120. Master Link included..