AFAM : AFAM Chain kit 520XSR 16/45 Super-Reinforced - Ultra-light Hard anodized rear sprocket €180.11
RENTHAL 486856 : RENTHAL Chain Kit 520R3 13/48 Reinforced - Ultra-Light Self-Cleaning Rear Sprocket €265.26
JT SPROCKETS JTA853.51BLK : JT SPROCKETS Aluminium Ultra-Light Self-Cleaning Rear Sprocket 853 - 520 €34.06