Professional Muffler Manufactory We, Hangzhou Helong Hardware & Machinery Co., Ltd., develop and manufacture quality mufflers and advanced exhaust system parts including front & end caps, inner caps, various muffler sleeves, stamped tips, baffle, different exhaust pipes, flanges, spark arresters and so on. Our products are produced base on customer specifications and requirements. They are all complied with international standard. We aimed at providing quality and satisfactory products & services to our valuable customer at a competitive price. All our work will be guaranteed in writing. We provide options in exhaust system modification to our customers and respect their choice. Trust from our customer is our treasure so we always pledge to do it right at the first time.