SL-9 Ultraslim Dynamo Front Disc Hub. Centre lock disc version of the SV-9 hub. The hub is suitable for all lights or accessories designed for 6V 3W hubs. Centre-Lock disc type. When used with 26” or 700c wheels the output can drop very slightly below 6V 3W at low speeds, but is 6V 3W at normal riding speeds.
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