The Ross NK-RP1-NEG is a 15 Volt regulator module for NK-RP1/P (50W max). The NK-RP1/P comes standard as a positive power rail supply. A negative power rail option can be installed as an upgrade by simply removing the front panel and inserting two NK-RP1-NEG option cards (required for NK-A16/32 and NK-V16/32 router levels).
The NK-RP1/PN comes pre-installed with two NK-RP1-NEG option cards to provide both a positive and negative power rail.