N.H. Rev. Stat. § 266:44
Every motor vehicle and trailer or any combination of vehicles, when on the ways of this state at night, shall have on the rear thereof, and to the left of the axis thereof, one lamp, displaying a red light visible for a distance of at least 1000 feet to the rear of such vehicle, and a white light illuminating the registration plate of such vehicle so that the characters thereon shall be visible for a distance of at least 50 feet, except that passenger cars manufactured or assembled after January 1, 1952, shall have at least 2 tail lamps, one to either side of the axis thereof. On a combination of vehicles, only the tail lamps on the rearmost vehicle need actually be seen from the distance specified. On vehicles equipped with more than one tail lamp, the lamps shall be mounted on the same level and as widely spaced laterally as practicable. All tail lamps on any vehicle shall be located at a height of not more than 72 inches nor less than 20 inches from the ground, measured from the ground to the center of the reflector, and shall be placed in such manner as to indicate the extreme width of the vehicle and load and to reflect rays of light thrown upon such reflector. The visibility of such reflectors shall not be impaired at any time. Whenever a vehicle is manufactured with multiple tail lamps or multiple bulbs or filaments in the tail lamps, each of the lamps, bulbs, or filaments and any other exterior lighting equipment with which the vehicle was manufactured shall be in working order.
RSA 266:44
1911, 133:7. 1913, 81:3. 1921, 119:6. PL 103 :6. 1931, 82:1. 1933, 105:2. 1941, 111:2. RL 119:8. RSA 263:13. 1979, 203:2. 1981, 146:1. 2002, 252:2, eff. May 17, 2002.