NRS 484D.125
Stop lamps.
1.
Except as provided in subsection 5, every motor vehicle, trailer and semitrailer, and any vehicle which is being drawn at the end of a train of vehicles must be equipped with two or more stop lamps, except that any vehicle manufactured before July 1, 1969, must have at least one stop lamp if the vehicle was originally equipped with only one stop lamp.2.
Except as otherwise provided in chapters 484A to 484E, inclusive, of NRS, the stop lamp or lamps must:(a)
Be on the rear of the vehicle, and if there are two or more than two must be as widely spaced laterally as practicable;(b)
Display a red, amber or yellow light visible from a distance of not less than 300 feet to the rear in normal sunlight; and(c)
Be activated upon application of the brake.3.
On a combination of vehicles, stop lamps on the rearmost vehicle only are required.4.
A stop lamp may be incorporated with a tail lamp.5.
The provisions of this section do not apply to towable tools or equipment.
Source:
Section 484D.125 — Stop lamps., https://www.leg.state.nv.us/NRS/NRS-484D.html#NRS484DSec125.