u clip is used to concrete construction. Its diameter is 12mm.The quality is good. ¹³ÃÃæÃÃÃøÿòã°å¡£²ú÷ÃÃÿÃÃý£¬Ã²¿Ã°´¿Ã»§µÃêÃóÃú²ú¡£