Cast Polished Brass These Bells feature traditional styling 8 Bells meet Coast Guard, ABYC, and NMMA requirements 200 cm mouth opening and striker mass no less than 3 of mass of the bell for use on vessels 12m 394,o to 20m 656,o in length Includes hanger and wall mounted bracket for easy installation Constructed of improved cast brass not lower grade spun brass Installs with two.