ENGLISH: Easy precise control of product application , very cost effective and cuts excess waste and increases the quality of the finished product: ENGINEERING , all considerations applied with mathematical technology including but not limited to viscosity, evaporation and vapor, friction, volume, specific flow at various angles, material to be used in manufacture of applicator or needle, air entrapment , product being applied with the applicator and I am sure I missed some. Overall an absolutely easy to use and awesome product very reasonably priced and saves you from wasting a lot of excess material dispensed by competitive products which do not produce the same professional results , even for beginners just getting started using the products. Thank you Loon for your wonderful environmentally safe products.