Right on Stu,nice to be able to see it visually(for me just a bit wider than a shoe box),10"that's what I see.
I can see it in my mind's eye(in Black)maybe you could post one

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Nice thing about them is they are more compact,same power as a 3 or 4B,
but in mono block fashion as people who are tight for space have alot more options without giving up on power,eye appeal and they are Squared

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The 4Bsst+3Bsst are very popular amps as we see quite a number of people don't need the power of a 7, 14 or 28

.I know size can be a major factor for peoples space.