We focused on maximizing your performance and the longevity of your CeramicSpeed Pulley Wheels when we designed the special Oil for pulley maintenance. Remember to add oil on the outside of the bearing seal after riding in wet conditions or washing your bike. If you are riding in harsh and wet conditions, we recommend that you choose the All Round Grease instead and grease your bearings from time to time. When using the Oil for maintenance, the recommended dose is 1-2 drops. Remember that the OSPW System has two lubrication points on the back cage plate to facilitate this process. The bottle contains 15 ml.