H4 stands for 4 cylinders.  2109CC is the displacement.

Dave B.

---- Pete O <pnoceanwesty@GMAIL.COM> wrote:
> Anyone using Odyssey batteries for their Vanagon?
>
> They are a top end battery and cost about $250. Supposed to be made with
> "virgin" lead, not alloy and provide a longer lasting more robust battery.
>
> They list the waterboxer as: 2.1 Liters 2109 CC H4.
>
> What does the "H4" stand for?
>