OurTGturbineventilatorsaremadeofstainlesssteel,andimporttheUBCbearingfromUSA.Allthepartsoftheturbineventilatorsarefinishedbytheprofessionalmoldingtools,theyareassembledaftercheckingbytheprofessionalequipments.Itworkswithouttheelectricitypower,theycanchangeourairconditionindoors,leaveusacomfortableenvironment.Also,whenusedinaworkshoporastoreroom,theycanadvancetheworkingenvironment,andthisimprovestheworkers'efficiency. Theballdiameteris620mmandthethroatdiameteris500mm.Ourventilatorsaremadeofstainlesssteel,andweguaranteetheusagefor15years.Itisabout8kg/setandtheUBCbearingsweusearefromtheUSA.Ventilatorscanexhaustthefumeandaircapacityisabout950-4000cubicmeterperhour.Wealsocandesignothersizesaccordingtoyourneeds. -ItisRainproofasAirexitsystemisdesignedtoprotectfromrain. -Safeasitdoesnotrequireelectricity. -Savecost,needonlynaturalwinds. -Nopollutionasitusesnaturalair. -Easytoinstallonanytypeofroof -Lightweight -Virtuallymaintenancefree. -Nonoiseasusingsupervenebush. -availableinstainlesssteelandothers.