How Do Heated Jackets Work?

Heated Jackets work by using thin wires that heat up when a low electrical charge is passed through. The most common type of power source for heated clothing are lithium-ion rechargeable batteries.
Heated Clothing panels are separated by a waterproof membrane making them safe to use in wet conditions.
Heated Jackets are designed to keep you warm and cozy but not get too hot and is safe for regular, everyday use.
For more Heated Clothing safety:
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[@JuanCarrero-ok3nx]

What size battery are needed for this jacket it says 25,35,45 degree Celsius maybe 25 I don't think about the other claims.