Minimum heating temperature
The lowest air temperature that a heat gun can produce when operating in normal mode, in other words, the lower limit of the operating temperature range. Accordingly, the lower this limit, the wider the range, ceteris paribus, and the more versatile the tool: after all, for different jobs and temperatures, you need different ones. Some modern hair dryers have the ability to "cold" blowing, without heating.
Cold air mode
This option allows you to completely turn off the heating element, leaving only the fan running, or reduce the heating temperature to a minimum of 50 °C.
The cold air mode is necessary for cooling heated parts. For example, a stream of cold air will allow you to quickly cool the seams of hot melt adhesive. Most often, the cold air mode is represented by a separate position on the temperature mode switch, while cold air will be carried out at one single speed. But some models allow you to turn off the heating element by hardware, in which case cold blowing can be carried out in a wide range of speeds.
Weight
The total weight of the tool. On the one hand, heat guns are held in the hands during operation, which means that a lot of weight is undesirable for them — heavy devices are less “agile” and tyre the operator more. On the other hand, too little weight can mean low quality materials, a small thickness of insulation and, accordingly, unsatisfactory safety performance. Therefore, in most modern models, the weight is at least 500 g, and in the most advanced models it can exceed 1 kg. Also note that some "heavy" hair dryers may have a design that allows you to install them on a flat surface during operation.
If there are additional nozzles in the kit, the weight of the tool without them is usually indicated.
