They do seem to be the same, with the exception of the B33 (235mm wide) and the B190 (249mm wide), the rest are 205-210mm, I felt my sit bones sitting on the edge of the metal frame, not on the back, but on the side.
@edscoble started
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They do seem to be the same, with the exception of the B33 (235mm wide) and the B190 (249mm wide), the rest are 205-210mm, I felt my sit bones sitting on the edge of the metal frame, not on the back, but on the side.