It's a partial 8 speed. Since you only have 6 cogs.. I'd say not that much. The 7th looks like a shimano piece to me. I imagine this is designed for a campy 8s freehub.
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1 Super Record bike, 1 Nuovo Record bike, 1 Pista, 1 Road, 1 Cyclocross/Allrounder, 1 MTB, 1 Touring, 1 Fixed gear