IPL uses a single intense pulse of energy which targets melanin. This only makes it effective on dark and coarse hair. This also makes it more painful for darker skin tones, as their skin will absorb more heat energy.
SHR, uses gentler pulses of energy at a higher frequency so the skin is heated gently. Only 50% of the energy is targeted at melanin, while the other 50% targets the stem cells responsible for hair production. This makes it a more effective treatment option for both coarse and fine hairs.
SHR is also a safer and more comfortable treatment option for clients with darker skin tones.