As a new member of GS series, Eleaf GS-A 0.8Ω Coil (Wattage Range: 8-15W Austenite) & Eleaf GS Air 1.4Ω Coil ( Wattage Range: 6-12W Kanthal ) uses innovative AST-steel for boosting flavor: AST is short for ALL-TIME STABLE TECHNOLOGY. This high-quality stainless steel is corrosion-resistant, rust-free, durable and has a very fast heating speed evenly distributed heat, bringing you first-class taste and vapor experience. Super austenitic stainless steel (AST-steel) is adopted as the coil material of GS-A, which delivers ultra rich and pure flavor in an instant and supports longer lifespan than ever. Also the AST-steel inside GS-A coil coupled with the chip-set inside Mini istick 2 will bring you the smart coil protection. The device stops output when it detects a lack of e-liquid, protecting the coil from dry hit.