... and a heat-fired, opaque, glazed surface. haohai ceramic road stud:1) body material: porcelain2) face: opaque glazed finished3) size:4",6 ... night4) can be used alone or with standard lineSpecification ceramic road studs:Strong resistance, greater than 160KN Strong reflective,Used in the ... are warmly welcome you come to visit our factory! Ceramic Road Studs (raised pavement markers,ceramic ...