That is a very antiquated Yandina combiner with a West Marine label. It's essentially a $3.75 70A Bosch type headlight relay in a Carlon electrical box with a small circuit board and a light. The current Yandina combiners are a better product but the Blue Sea a a very, very nice piece of equipment with robust terminals and fully epoxy sealed and it can handle 120A continuously. It can also do start isolation a nice feature for boats that have solar etc.. They both essentially do the same thing which is parallel banks based on voltage. If keeping the Yandina feed all charge sources to house bank and let it combine with the start bank. This taxes it the least and will limit relay cycling. This is a best practice for all combining relays.