All you need to make your own is a float charger, motorcycle/car battery, a 1 amp fuse and the same terminal plug to connect MP40. Float chargers keeps the battery charged at all times without damaging it by overcharging. I used a regular car battery rather than a deep cycle battery because of costs and warranty. Unless you plan on continually draining your battery to run the Vortechs then a regular car battery from Costco will do. 5 years warranty as well. This setup can run your Mp40 for days.