Stovax Professional XQ Stove & Fireplace Chimney Systems Key Features: – Easy to install Twist-Lock system – Weatherproof, fully sealed components – Suitable for internal & external applications – High density, mineral wool insulation – Made from high grade stainless steel – 316L stainless steel inner wall for the highest corrosion resistance – 304L stainless steel outer wall in an attractive, polished finish.