“Tire width,” when applied to pneumatic tires, shall mean the diameter of the cross–section of such tires as customarily measured and rated by the manufacturers of motor vehicles and tires.

Source: SDC 1939, § 44.0336 (6) (e) as added by SL 1943, ch 158, § 2; SL 1947, ch 192; SL 1953, ch 234; SL 1957, ch 223, § 2; SL 1959, ch 260, § 2.