This is a Turbostart 16v Step Up Transformer. This allows you to charge 16v batteries off a 12v system without any added modifications. I ran this on my system for years and it worked flawlessly. My system consisted of 2 18" MT's, 2 Visonik V4000XD's, and 4 Turbostart batteries. As you can imagine this system drew lots of amperage, and the transformer kept up with it no problem.
Let me know if you have any questions!
Price - $100