To answer this question, one must understand the principle of laser .
The most effective and popular are alexandrite laser and a diode laser.
You can choose between alexandrite and diode lasers: in the first case, the setting is more powerful and fewer procedures , and in the second the price is slightly lower, but more sessions will be required.
Alexandrite laser epilation
Powerful apparatus with alexandrite head and 755 nanometer wavelength. This wave is maximally absorbed by melanin and minimally by hemoglobin. The energy flux per pulse is 100 J / sq. see The frequency of the impulses is significantly higher than when using ruby equipment - up to 10 Hz, the duration of each impulse can be from 0.25 to 300 ms. High efficiency is combined with a reduced risk of burns - the devices are equipped with cooling devices for the skin.
In the hands of an experienced master, the alexandrite laser works wonders, but it is important to trust this procedures only to a qualified and attentive cosmetologist.
Argument s for:
The wavelength is over 800nm in the NIR and the radiation can handle even light overgrowth , including on tanned skin. The pulse duration is 5-30 ms, the energy flow is up to 60 J per sq. see, frequency indicator - up to 2 Hz. This variety is inferior to alexandrite in terms of effectiveness , but is also popular.
Instant smoothness is not to be expected, hair loss continues for a week.
More treatments have to be done compared to alexandrite laser
For details on choosing a laser, see this article https://otrazhenie-clinic.ru/blog/kakoj-lazer-dlya-epilyaczii-samyj-effektivnyj-i-luchshij/
There are other lasers, about them are written in this article https://otrazhenie-clinic.ru/blog/epilyaciya_vidy/
Health and beauty!
By far the most effective laser for hair removal is the diode laser. But remember - any laser hair removal is a temporary type of hair removal. Keep in mind that laser hair removal is only effective for dark hair.