ZLINE's professional black stainless steel is truly unique in the industry. Each piece is hand cut and crafted utilizing 304 grade stainless steel which accomplishes a sophisticated, ‚Äúpiano black‚Äù finish through a technique called bluing. The technique of bluing has been used historically to change the finish of gun barrels. The proprietary black stainless steel finish is hand soaked to a specific ratio which depicts the final and exact result of the black stainless hue. The industrial design of the RTB is executed through precise lines and detailing done with a precision laser. Each model includes Italian burners delivering over 65,000 BTU's, including a durable, solid-piece Cast Iron Grill.