The Hair Regrowth Laser Comb, Laser Comb Professional 12, Hair Loss Comb works with a process of photo-bio-stimulation. This process transfers the laser energy to the cellular energy increasing the ATP to mitochondria which increases the growth factors within the dermal papilla stimulating cell proliferation of the hair matrix. In short, it uses the laser light energy to energize and revitalize the hair follicles promoting new growth and reversing the thinning process. As per the instructions, one must comb the hair for almost 8 minutes daily front to back and then side to side, moving the comb in ½ inch increments every four seconds. The comb is used for three or more days per week but only after shampooing when the hair is free from styling products. The comb is prescribed to be used for 12 weeks before having an awesome result.