Excalibur® 309/309L-15 stainless alloy,s Q2 Lot® - certificate showing actual deposit chemistry and calculated ferrite number (FN) available online. Designed with low carbon levels to help eliminate carbide precipitation in high temperature service. Flux coating is fast freezing for vertical down welding and slag is self-peeling for easy removal. Smooth bead appearance with evenly spaced ripples and flat face. Application, joining stainless steel to mild or low alloy steel.