The automobile mainly is by has the good elasticity and the anti-compression deformation, bear aged, the ozone, the chemical action, the wide application temperature scope (- 40`C~+120`C) three Yuan second grade third rubber (EPDM) rubber with the packing to become spongy with bonds densely becomes, contains the unique metal jig and the tongue shape buckle, firm durable, favors the installment, already for a long time formed a complete set with each big automobile manufacturer.