DERNORD12V 400W Immersion Heater Submersible Water Heater Element Stainless Steel Heating Element with 1 Inch NPSM Fitting Double U Type

I measured the element with connecting bars attached. Ohms measured 0.5 ohms, 12 V/0.5 ohm=24 amps, 24x12=288 watts. This will give a decent amount of heat to keep water from freezing.

I replaced the 120v element in a Kuuma heater with this unit. Ran 8 gauge power cable to it and it does work.But it takes forever to heat a 10 gallon water heater from cold. Like 6 hours. The 120v element heated the tank from cold in 45 minutes.Once hot it maintains temp okay. Each cycle is about 1 hour. That being said its drawing 28 amps during that time. Overnight that depletes 40% of my 600ah battery bank. Not what I was hoping for.At 28 amps I really wish this got way hotter. I cannot decide if this is performing better than when I ran the 120v element off my inverter. I believe overnight depletion is around the same. I am really interested in trying it at 24 volts, but that an experiment for future me.So if your using this in a vehicle, and that vehicle is running the engine every day you should be fine. And 28amps is way less stress on the batteries than 160amps is from an inverter. Just plan you showers accordingly as the recoup time is LONG.I will update long term performance a few months from now.

I have used these for years and never had one fail. With the two elements, they can be configured for half-load (one element), full load 12V (factory config with parallel jumpers) or full load 24V (move jumpers to series the elements). As such, they are perfect dump loads for solar and wind turbine use and can store energy as hot water. The 1" NPT fittings fit many common water heaters.

it works, simple to install, drilled a hole in my water container and hooked it up to my batteryits gets super hot, takes a bit longer to warm the water than i thought it would tho, but i didnt know what to expect.

Appears that I should work as intended, looks like good quality.