You need the Mavic spacer on first, so it now converted to 10 speed spacing, then you put the spacer that was provided with the cassette on after.
If a cassette doesn't come with the spacer (like the Tiagra one), you won't need it.
Really helpful, thanks a lot.
@jakemcree started
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You need the Mavic spacer on first, so it now converted to 10 speed spacing, then you put the spacer that was provided with the cassette on after.
If a cassette doesn't come with the spacer (like the Tiagra one), you won't need it.