... efficiency over 99.8%. light weight,easy to install. special air passage design, 1)we are the outside trade company.2 ... of high quality material3)Used to prevent againest leakage4)Keep air clean5)All parts are under rigid quality control befor shipment6 ... markets:north America,south America,Eastern Europe,Southeast Asia,Africa,Oceania,mid East,Eastern Asia,western Europe etcif you need some request ...