Many of these machines come with their own skin gel, which means it’s best to use this gel instead of another brand. If your device does not come with its own gel, read the directions to make sure it does not require a special type of gel. If it comes with no gel and gives no recommendations, you can use any good quality skin gel prior to treatments; we recommend Silk’n Slider Hyaluronic Gel. But always use some type of gel with an RF machine because it is safer and more effective on the skin.