Snatch 2a Unidentifiable black box under drivers seat

I'm currently stripping out a Snatch 2a and have found some sort of electrical item under the driver's seat next to the batteries. It may be something very obvious but I can't tell what it is or what it does. can someone tell me if it's necessary anymore as the vehicle works with or without it. I understand this is the vaguest of descriptions but I've added some photos which may help. One is attached and the rest are on the link below (as they take so long to upload on here).

https://photos.app.goo.gl/8MJYZ8kjqXF5wgDt6

Cory

Does it have twin alternators? Could be the switch box for the aux batteries (like a split charge system)

its not of the vehicle or age

Hi Cory

I'm new to all this but have just got a TUL HS FFR WW. I managed to get a PDF Copy of the Parts Catalogue which is my primary reference document at the moment. If you don't have it I can send over and it may help you?