Dermaroller needle Size: 0.22X0.2mm, 0.22X0.5mm, 0.22X1.0mm, ... .0mm, 0.22X1.5mm, 0.22X2.0mm2. Definition: The dermal roller is the best and most effective device for deep transdermal ... push them aside, forming tiny mico-pores. While the dermal roller over the skin the previous applied substance (cosmetic only) is ... acts like a longterm depot to retain the active substance derma roller