Road spline, no line, 50mph, 12m wide, with medium traffic level. Designed to be 0.2m over baseboard level for correct car height. Texture derived from those by cgtextures.com and Andi06. To diagram . See http://www.legislation.gov.uk/uksi/2002/3113/schedule/6/made and http://www2.dft.gov.uk/pgr/roads/tss/tsmanual/trafficsignsmanualchapter5.pdf for details.