Tom Walker wrote in a message to Roy J. Tellason:

-> What,  one with standard as opposed to marine-style terminals?  Any other
-> variation,  and it's not an 8D any more,  as that designation
-> refers to the
-> size of the battery...

 TW>  The size of hte Battery Case. It was also used in commercial
 TW> Equimpment, Cranes etc, and those 8D's had standard automobile
 TW> terminals but were still 8D's. 

Yep.  I know of one fire engine in particular that took two of them.  Lots
of stuff out there took bunches of group 31,  in parallel (most of the big
rigs use 3 or 4 of those) or sometimes 4 of the bigger 6V units in
series-parallel.

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