I think I bought one of the 6-bolt conversion kits to get the one I use, but you can get the lockrings separately, new: https://www.amazon.co.uk/Shimano-SM-HB20-Centerlock-Rotor-Lockring/dp/B00JXNTVHI/ref=asc_df_B00JXNTVHI/
@hippy started
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I think I bought one of the 6-bolt conversion kits to get the one I use, but you can get the lockrings separately, new:
https://www.amazon.co.uk/Shimano-SM-HB20-Centerlock-Rotor-Lockring/dp/B00JXNTVHI/ref=asc_df_B00JXNTVHI/