edco's lock nut rings are high-quality and can be used with Shimano tools to fix the lock nut ring on the free body hub. The lock nut rings are designed for Shimano free body hubs. They can be used to fix Shimano/SRAM cassettes or the edco Monoblock with either 11T or 12T.
The edco development "10/11 conversation lock nut ring" is something special - you can use this lock nut ring (red color) to fix a 11-speed cassette on your 10-speed free body hub. As a result you can still use your 10-speed wheel set with an 11-speed cassette and your 11-speed shifting group.