The photo below shows the cabin ring installed on the front port bulkhead. Such rings can be seen on old boats and this one is made in the style seen on wooden boats where the ring mounting is bolted through the wooden cabin wall. This matches the roof rings shown in an earlier post.
Note the grooving of the steel to replicate wooden planks.
In addition to being decorative these rings provide usefull rope attachments.
The brass fitting above is a plug into a 1/2" BSP socket to allow 12V cables and the TV aerial if required to be fed through the cabin wall. The socket is tilted down to drain ntaurally.
This was adopted as a simple but versatile alternative to the usual prominent and glaring external fittings for routing TV aerial cables into a cabin.