S.C. Code § 56-5-4610
Every reflector upon any vehicle referred to in Section 56-5-4580 shall be of such size and characteristics and so maintained as to be readily visible at nighttime from all distances within five hundred to fifty feet from the vehicle when directly in front of lawful upper beams of head lamps. Reflectors required to be mounted on the sides of the vehicle shall reflect the required color of light to the sides and those mounted on the rear shall reflect a red color to the rear.
Front and rear clearance lamps shall be capable of being seen and distinguished under normal atmospheric conditions at the times lights are required at a distance of five hundred feet from the front and rear, respectively, of the vehicle.
Side-marker lamps shall be capable of being seen and distinguished under normal atmospheric conditions at the time lights are required at a distance of five hundred feet from the side of the vehicle on which mounted.
S.C. Code § 56-5-4610