M1 HIGHWAY, GRAYSTON (A) SITE NUMBER : BB13-77 DESCRIPTION : High traffic flow Linking Johannesburg and Pretoria, just before the Grayston and Corlett drive Off ramp. MAX SLOTS PER DAY- 2170, DURATION OF SLOT -30 SECONDS, MAX No of ADVERTISERS PER LOOP – 8 SIZE: 3M (H) x 12M (W) TRAFFIC : OMC IMPACTS : 6 447 890 GPS CO-ORDINATES : -26.1145, 28.07552