ventilation block

perforated block, made of concrete or other material, used in permanent wall openings for ventilation and natural lighting of buildings

en-GB/ˌvɛntɪˈleɪʃən ˈblɒk/
en-US/ˌvɛnəˈleɪʃən ˈblɑk/

دسته بندی ها:

building materialconcrete block