The Yocan Flat Slim features three easy-to-use voltage settings out of the box. These voltage levels can be controlled using the square-shaped power button located on the top part of the vape pen battery. The Yocan Flat Slim features three easy-to-use voltage settings out of the box. These voltage levels can be controlled using the square-shaped power button located on the top part of the vape pen battery. The lowest setting is tuned at 2.6 volts for those looking to vaporize their wax concentrates and essential oils to extract its flavorful and aromatic active ingredients. The middle voltage setting clocks in at 3.2V to create tasty and fragrant clouds of vapour with slightly increased potency. Finally, the highest temperature level of 3.8V unlocks the full potential of your materials and allows you to extract its highly-potent active ingredients.