Esab Coreweld C6 LF description: Coreweld C6 LF is a low manganese emissions, high efficiency, metal cored wire developed in response to new EPA regulations and guidelines from ACGIH (American Conference of Government Industrial Hygienists) for Manganese fume exposure limits. With all the same enhanced features of ESAB’s standard Coreweld C6, Coreweld C6 LF has more than 50 percent lower manganese content and is designed to provide excellent operating qualities while significantly reducing the manganese levels in the welding fumes when compared to standard metal-cored electrodes of the same classification.