hose 1,quality assurance 2,superior services 3,reasonable price 4,promptly supplies hose 1 Material :NBR ,Silicone,NR,SBR,EPDM,etc2 Types of O-ring,E-type,U-type,can make on customer's request.3 We promise the high quality but competitive price for our products .4 Certification level:SGS,FDA,SGFB,UL