Shanghai Sona Shock Absorber Co.,Ltd is an international and professional manufacture which engages in research & development, production and sale of rubber expansion joint. As the leading company in rubber joint field, we have developed series of newly-designed products by absorbing advanced scientific technology and processing experience from abroad and our experts' continuous research, it proved that our products enjoyed a good market both in domestic and overseas for its high quality. Our products have been successfully exported to so many countries.