"To penetrate the skin" means to go through or enter the outer layer of the body that covers and protects the underlying tissues and organs. Full definition
Product absorption: While it's true that products will more deeply penetrate skin through the channels created by the needles, this is not necessarily a good thing. (theeverygirl.com)
It's also anti-inflammatory and is able to penetrate the skin more effectively than other essential oils, ensuring a deep and thorough treatment. (azhealthyfamilies.org)