We Make these Nitrous Bottle Heaters in a "Bath Type" or "Spa Type" where you put water in, place your bottles in and then set the digital temperature controller to desired temp & walk away. It maintains temp within +/-2 degrees all day. It runs off of a standard 110 outlet and the amp draw is minimal so a small generator has no issues running this. We have them in a 10# and taller 15# version. The standard finish is raw aluminum or we can have them powdercoated black for $50 more.