The Allen-Bradley 142758 is a non-regenerative SCR cell assembly kit designed for seamless integration with Series B 1395 DC Drives and MKVA systems. This versatile kit supports drives rated between 125 and 737 horsepower across various voltages from 230 to 660 volts AC, featuring essential upper and lower snubber boards for enhancing system stability. The snubber boards, identifiable by part numbers 133736 and 129891, or 161502 for MCC styles, are engineered to suppress voltage transients, safeguarding the SCRs, and can be directly mounted onto the armature bridge bus bars of DC drives, ensuring reliable performance within a temperature range of 0 to 50 degrees Celsius.