There’s a diagram in the first PDF on that page. It’s the width over the bottom bracket cups, which will be specific to your frame and cups.
I’d expect most road bikes to need the shorter one.
Thanks!
@Alf0nse started
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There’s a diagram in the first PDF on that page. It’s the width over the bottom bracket cups, which will be specific to your frame and cups.
I’d expect most road bikes to need the shorter one.