Ob chav tis expansion chav kuj tseem hu ua ob chav tis folding chav tsev, kev siv galvanized high-strength square yeeb nkab, galvanized Lub kaum sab xis hlau thiab lwm yam khoom siv lub teeb steel los ua tus ncej, tiv thaiv corrosion ob-sided xim steel composite phaj li phab ntsa, kev siv lub pob khawm muaj zog ntawm lub thav duab los txuas, tom qab kev xam pom, tuaj yeem nthuav dav lub tsev qhov chaw ntawm lub tsev sai sai.Qhov chaw ntawm lub tsev nthuav dav yog ze li peb zaug loj dua ua ntej kev txhim kho.Yuav ua tau 20 ko taw, 40 ko taw nthuav dav chav, kuj tuaj yeem kho raws li cov neeg siv khoom xav tau.Nws yog ib hom tsev nyob nrog cov ntsiab lus siab dua ntawm cov tsev ntim khoom nyob.
Ob chav tis nthuav dav siv pob khawm los txuas ua ntej ntawm phab ntsa, thiab qhov ntim tom qab compression txo qis heev, uas yooj yim rau kev thauj mus los.
