Ntau qhov zoo ntawm cov qhov rooj hluav taws steel ua rau lawv tuav lub lag luam loj hauv cov tsev pej xeem. Hlau hluav taws qhov rooj steel qauv tuaj yeem xyuas kom meej tias nws tsis yooj yim rau kev cuam tshuam deformation thiab sab nraud quab yuam puas, tuaj yeem siv tau ntev, tsis tas yuav hloov.

180 feeb hluav taws qhov rooj,hluav taws kub ntsuas ob qhov rooj,hluav taws kub ntsuas qhov rooj qhov rooj loj,180 feeb hluav taws qhov rooj,1 teev hluav taws qhov rooj, hluav taws kub ntsuas hlau qhov rooj,hluav taws nyob qhov rooj zawv zawg,burgalary & hluav taws nyob qhov rooj,hluav taws kub ntsuas qhov rooj qhov rooj loj,ul teev hluav taws qhov rooj kho vajtse,hluav taws nyob qhov rooj zawv zawg,hluav taws qhov rooj rau kev lag luam textile,180 feeb hluav taws qhov rooj,1 teev hluav taws ntsuas qhov rooj,hluav taws kub ntsuas qhov rooj qhov rooj loj,niaj hnub grey hluav taws nyob qhov rooj nkag,hluav taws nyob qhov rooj zawv zawg