This product is composed of two 11 teeth 7075 aluminum pulleys with full ceramic sealed bearings.

If you cannot find OSPW that fit you current derailleur, theses pulley Ceramic Pulley wheels are made for you ! 
Very easy to mount, and fit with lots of references :

Compatibility example :

Compatible with Shimano groups that have 11 and 12 tooth pulleys

- Shimano 105/ Ultegra / Dura-Ace 11Speed

Designed by our French Engineers these NOVA Ceramic Pulley Wheels for rear derailleur improve the fluidity of your transmission, enhance efficiency to satisfy the most demanding. Made in very high-end materials: 7075 Aluminium and ceramic bearings.

These option enable you to Upgrade your derailleur with a more affordable price Two Oversized aluminum wheels, which coupled with ceramic bearings decrease the chain winding angle with minimal friction.

How To Install Nova 11T Ceramic Pulleys on your bike : https://youtu.be/MzsA9yMOM-U

Features:

Weight : 11 g per pulley

Watt saved : 3 W

International shipping.