Milwaukee® 9" Type 27 Grinding Guard Assembly is designed for 6086-20, 6089-20 grinders, 6088-30, 6090-50, 6086-20, 6089-20, 6089-30 9" grinders, 6088-30, 6089-31 7" and 9" grinders with lock-on, 6088-31, 6089-31 7" and 9" grinders and 6089 sander. Grinding guard can be used for grinding wheels without threaded hubs.