Space-Age Material Reflective Water Heater Blanket - R3.5

There is enough tape in the package to install the blanket properly

Fiberglass has a high flame rate and when this product is used as a water heater blanket it is safe. It should not be used for anything other than its intended use.

No it would not be safe. Smoker temperature would be too high.

Sure looks like the R-value is only 3.5, not 19. Fiberglass batts have R-value of about 3-3.5 PER INCH, and these bats are only 1" thick. Have no idea why that R-19 value is out there (description indicates "R19 Equivalant," but does not explain "equivalent." Expect only R3.5 from this product. I do not see that the "reflective" component of the blanket would add any insulation value, because there has to be empty space between a heat source and reflective barrier to have any insulation value.

Yes . I bought this for a 40 gallon electric water heater and i used it to insulate the tank from 8 inches up from the bottom of the tank and it works very well saving approx 30% electricity usage over the month and the water flows much hotter

If you're concerned about whether an insulation blanket might make your water heater too hot during the summer and maybe burn something out, don't worry--the water heater's thermostat will keep the water temperature inside the tank where you set it, all year.

It's fiberglass so it can withstand maximum temperature your water heater can produce.

FYI, a reflective material like aluminum only provides insulation value (resists the flow of heat from one location to another) if there is open space between the source of heat (water heater, in this case), and the reflective surface. If the reflective surface is in direct contact with the source of heat, it provides virtually no insulation value. Remember, aluminum is used in cookware, in which the idea is to transfer heat from the heat source to the substance being heated; in this use, you do NOT want any insulation effect. Bottom line: reflective material, like aluminum, only has insulation value if it is not in contact with the source of heat, but there is empty space maintained between the heat source and the cooler, surrounding environment.

R-value rating of 3.5. R-value is a measure of resistance to heat flow: indicative of how many BTUs of thermal energy will flow through a one square foot area hourly, for every degree Fahrenheit of temperature difference across the insulation. Said R-value of the blanket installation can be increased by adding air gaps, multiple layers, and additional barriers such as films, foils and bubble wraps. Readily, one can achieve R-19 and higher values - equivalent to building envelope values - with lightweight sections.

Online it stated R19, but the packaging had R3.5 on it. I returned it