14T VS 12T. 1 x Derailleur Pulley. Narrow Wide Teeth Design, Prevent the horizontal swing of the chain. (2) Stainless Steel Shell& Ceramic Bearing For Axis ,More durable and resistant. Support 9/10/11/12 Speed Bike.
EffiFish Bike Rear Derailleur Pulley,Road Bike Ceramic Bearing CNC Pulley Rear Derailleur 12T Wheel Wear And Resistance High Transmission Efficiency(12T Black)
Impalapro Bike Set of 2 11T Jockey Wheel - Pulley Wheel for Derailleurs for Bikes Ultralight and Durable with Ceramic Bearing for MTB or Road Bike - Derailleur Pulley - Shimano Derailleur(Black)
Brrnoo Bike Ceramic Pulley Aluminium Alloy Rear Derailleur Guide Roller Part Accessory Smooth Ball Bearing Wheel 2pcs (11T)
Sram GXP Pressfit Road bike Ceramic bottom bracket
MEIJUN 12T Aluminum Alloy Bike Pulley Wheel Guide Wheel Mountain Bike Ceramic Bearing Rear Pulley Durable Smooth Shifting for 7/8/9/10 Speed Bikes Multicolor Lightweight
MEIJUN 18T Aluminum Alloy Bike Pulley Wheel Guide Wheel Mountain Bike Ceramic Bearing Rear Derailleur Pulley For 18T Mountain Bikes Multicolors 4/5/6mm Axis