This high - grade Shimano pulley set is designed for use with Shimano Ultegra RD - 6700 10 - speed rear derailleurs. It's a genuine Shimano replacement part. This Tension & Guide Pulley Unit is an 'A' match for Shimano Ultegra RD - 6700 - A - G, RD - 6700 - A, RD - 6700 - G, and Shimano 105 RD - 5700 - A, meaning the parts are the same in materials, appearance, finish, and size. If the correct unit isn't available, you can use units from Shimano Dura - Ace RD - 7900 and Shimano 105 RD - 5701. These are a 'B' match, which means they're usable but differ in materials, appearance, finish, and size.

Using this Shimano pulley set is straightforward. First, make sure your rear derailleur is one of the compatible models mentioned. Then, carefully remove the old pulley unit and install the new one. It's a good idea to use the right tools to avoid any damage. As for maintenance, keep the pulleys clean. You can use a mild degreaser and a soft brush to remove dirt and grime. After cleaning, dry them thoroughly. Also, check the pulleys regularly for any signs of wear and tear. If you notice excessive play or unusual noise, it might be time to replace them. When storing the pulley set, keep it in a dry place to prevent rusting.