Reflector Tab： also known as the contour marker, the English name Delineator, which is a traffic safety facility that is set along the edges of both sides of the road, is used to display the outline of the road boundary, guide the normal driving of the vehicle, and has retroreflective performance. Functionally speaking, the contour marker is a sight-inducing facility. According to the different setting conditions, it can be divided into two types: free-standing contour marks and attached contour marks. When there is no structure on the roadside, the outline is a column type, which is composed of a column and a retro reflector, and is independently set in the roadside soil shoulder. Its main structure is a triangular cross-section column; when there are structures on the roadside, the outline is It is attached and consists of a retro-reflector, a bracket and a connector. Depending on the structure, the contour markers can be attached to the corrugated beam guardrail, concrete guardrail, tunnel side wall and cable guardrail, respectively.