About product and suppliers:
            40,211 china vent products are offered for sale by suppliers on Alibaba.com, of which valves accounts for 8%, hvac systems & parts accounts for 7%, and waterproof membrane accounts for 1%. 

A wide variety of china vent options are available to you, 

There are 39,492 suppliers who sells china vent on Alibaba.com, mainly located in Asia. The top countries of suppliers are China, Hong Kong S.A.R., and Taiwan, China, from which the percentage of china vent supply is 99%, 1%, and 1% respectively.