Mounting of the pump(s) can be done individually or in a dual configuration. For both configurations all required material is included.
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Please note: In order to use the single version, screw plugs must be ordered separately.
That doesn't make sense...
To run a single pump you require a g1/4 stop fitting but to run with 2 pumps you don't.

Yea, but the first statement is implying that you already have everything you need, whether you want to run dual or single pumps, but the second statements suggests you need more than what's included to run single.
Or am I missing something here?