Before buying any product, you should know some basic features that will determine the product matching to your preferences. Unfortunately it is not always easy to have a complete preview of the product because it is usually difficult for buyers to do a test instantaneously or over time. So we rely on feedback from reviewers and our beta testers, and also on the user experience of customers and friends who have bought this product and have formed an opinion that we use as a type of consulting. Then we can determine specifically what it is capable of offering at its peak, as well as some general guidance for you to tell if the product is suitable for your style of vaping. As for the mouthpiece, we need to know the user’s style of draw, weather it is mtl or direct lung. Usually we understand this from its size in general, but the main aspect is the internal diameter of the exit. Height is usually a matter of taste and general appearance but also in differentiation of the draw. Usually it does not change the flow of vapor from mtl to open dl and vice versa. Some models, mainly related to mtl mouthpieces, have been designed for easy use and easy cleaning, always giving priority to the configuration. of steam to the best in terms of taste as a function of the density of the steam that passes through it. The material usually does not change the final result, but contributes a lot to the external appearance – matching of the whole set.