N.J. Stat. § 39:4-108: Semaphores

Semaphores shall have four vanes or sides, the stop vanes having a red field with the word "stop" plainly visible thereon, and the go vanes a green field with the word "go" plainly visible thereon.

When used at night, semaphores shall be equipped with red and green lights, corresponding with the vanes or sides, and with the same meaning and visibility as electrically equipped signals.