From traditional copper wrapped kistky, Delrin, Econo Almost Electric, and Almost Electric, I stock them all. Traditional copper wrapped depend on the multi wrap copper to hold the heat. Delrin refers to the plastic handle, these brass head kistky require often heating from the flame. Econo Almost Electric Kistky have a larger tip, and hold more wax. Only the tip should be put in the flame. Almost Electric Kistky are the best for holding the heat, the brass head should beplaced in the flame for a short time, over extended heating tome will cause the plastic stem to melt. As always for no soot I use an Alcohol Lamp and 91% alcohol. Soot will block kistky.