The Yocan Uni Pro is a box mod that features universal compatibility with oil atomizers of all lengths and sizes, taking your customization to the next level. A variable height slider and an adjustable diameter dial allow you to fit all sorts of different oil atomizers into the device, and a 10-second preheat function with a 2.0V-4.2V voltage range adds high-grade performance to an already impressive list of functions. 650maH.