This 13-tooth upper and 19-tooth lower OSPW System has been platform proven aat races like Paris Robaix, Strada Bianche and CX World Cups.

The system is built for gravel and cross disciplines and meets the needs for durability, low friction and longevity.

The four spring tension setting allow customized setup based on ride conditions, wnd the hand-built OSPW System offers custom molded carbon fibre cage for lightweight and durability.

CeramicSpeed OSPW System reduces friction 35-40% over stock pulley configuration.

Compatible with the 2x specific RX-820 and RX-825 derailleurs.

If you are using a 1x you can use a 36T cassette maximum.

Note: Only the H (high) spring tension hole should be used with the RX-825 Di2 derailleur.

In the box:

• Complete OSPW X for Shimano GRX RX-820 2x12 system.
• CeramicSpeed Oil for Pulley Wheel Bearings, 15ml dropper bottle.