JT DRIVE CHAIN : DID/JT Chain Kit 420D 13/47 (No OEM Ratio) Standard - Steel Standard Rear Sprocket €41.65
D.I.D : DID/JT Chain Kit 520ERT3 12/52 Super-Reinforced - Ultra-Light Self-Cleaning Rear Sprocket €113.39
RENTHAL 486560 : RENTHAL Chain Kit 520R3 13/48 Reinforced - Ultra-Light Self-Cleaning Rear Sprocket €270.83