A. Equipped with German-made solenoid with safety valve, assure quality, silence and safety. B. Precision needle valve provides stable and accurate CO2 output. C. Made with stainless steel, anti-rust. D. Hand air-tighten design, no tool required. E. Dual gauge indicators show different pressure volume, one indicate the pressure inside the bottle, and the other one shows the depressurise power. F. With solenoid to work with a timer.