... bearing, double stainless steel pearl, more durable8.imported type B belt from korea, wider and thicker 35% ... longer circle time than the type A belt commom used in this line9.Safety net ... performance test, fan blade turning speed test, input air test, vehicle efficiency test and motor current test.11 ... 53.8440001380*1380*45080 New designgreenhouse/poultry air cooler/air cooling system z