I have been corresponding with a fellow AIM user and he had never heard of the Seawell group up in Seattle in the late 1970's so I put up a couple of scans of their offering on this site

One of their more humerous product titles was their Little Buffered Motherboard.  It is a great product and I still have two of them for using their Prommer II and their RAM/ROM expansion.  Unfortunately, I didn't retain their disk system as it was quite a luxury to have one of those back then!
little buffered motherboard front

little buffered motherboard back