Extra Needles per Head The Skin Roller has 540 needles per roller head, in comparison with the standard roller that has less than 200 needles per head. With extra needles, you will have greater penetration in much less time. * Thinner Needle Thickness The needle thickness is 0.20mm, in comparison with the standard needle thickness of 0.25mm, which means you should have much less discomfort throughout needle therapy. * Needle shape leads to less discomfort The diamond shape of the 540 Needles Skin Roller leads to less pain compared to the standard round shaped needle of other skin rollers. This is because the thickness of the spherical-shaped needle is twice as large as the diamond shape needle of the 540 Needles Skin Roller * The size of the roller depends on the skin"s (epidermis) thickness of treated area. The needles are not supposed to reach the dermal (dermis) level deeper than 0.5mm. Skin thickness varies from tens shares of millimeters to 4 millimeters. * FULL INSTRUCTIONS PROVIDED, FOR MORE DETAILS VISIT OUR WEBSITE SKIN BEAUTY SOLUTIONS