For example, customers may wish to order more of
The "M" as a Surge Protection is no longer an option. That "M" USED TO represent a lower surge suppression option than is now available with the "J" option. The "J" surge suppression option specifies an improved 320 joule/9500 amp surge protection rating instead. So change the aforementioned part number to D120-1.0-STJBK Jxx
and Customer should be good to go.