RK Takasago Chain 12-529-120GD Sprint Race Series U-Ring Chain GB520TRU 120 Link GoldRK Racing Chain Series apply RKs only technology of Ultra Thin Seal, U Rings or UW Rings, where the thickness of seal is less than 50% of the common seal, make it possible to design a Sealed Chain with the weight of a Non Sealed Chain. Application of Sealed Chain on Races can minimize the elongation of the chain which maintains the meshing precision between chain and sprocket, keeping high transmission efficiency throughout the race. RK Racing Chain