Power/temperature control
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Joint. In models with joint adjustment of power and “degree” of air flow, the parameters change at the touch of a button. Hair dryers usually have several fixed values of blowing intensity and air temperature.
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Separate. Separate heat and temperature controls give you more freedom of choice when using your hair dryer and styler. The parameters of the flow force and temperature for hair dryers with separate adjustments change separately, which allows you to count on the optimal values of power and “degree” of blowing to avoid overdrying your hair.
Power modes
The number of power modes provided in the design of the tool.
This parameter is relevant primarily for hair dryers of various types (see "Device") — in models of another type, the main point is the temperature modes, see below for them. And in hair dryers, the number of power modes is, most often, the number of speeds at which the “blower” can operate.
The abundance of speeds allows you to choose the best option depending on the current task (quick dry, delicately style), hair type, etc. At the same time, the abundance of adjustments complicates the design and affects the price. Therefore, for domestic use, 2 – 3 modes are usually quite enough, and sometimes one is enough.
Note that in single-speed hair dryers, the number of modes may not be indicated at all.
Brush diameter
The diameter of the brush used in the corresponding tool (see “Device”), more precisely, the diameter of the cylinder from which the brush hairs “grow”.
For different hair lengths, different types of hairstyles and styling methods, the optimal sizes of brushes will also be different — in some cases, a small diameter, 20 – 25 mm, is more convenient, in others large brushes of 30 mm or more will be more convenient. However, this parameter is relevant mainly for professional use and work with long hair, complex hairstyles, etc. If the tool is bought for normal household use without any frills, the diameter of the brush is not so important.