Road marking spline, Give Way - Roundabout. Designed to be at baseboard level. Texture by Andi06. To diagram 1003.1. 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.