Mag drive coupling has magnets internal to the pump which is connected to the driving gear. The magnets can be ferrite type, sintered neodymium magnets(higher magnetic strength), and SmCo magnets(with temperature up to 350 Celsius).
6 indicates that the steel wire rope is a 6-strand steel wire rope;37 indicates that there are 37 wires in each steel strand, which is a point contact structure.