Cua thep chong chay con duoc goi la cua thoat hiem, cua thoat hiem cau thang duoc lam tu thep nguyen chat, 2 tam thep ghep vao nhau chac chan. Do chong chay cua san pham cung duoc chia lam nhieu cap do khac nhau. Voi moi cap do chay khac nhau thi bao gia cua thep chong chay khac nhau cung nhu thoi gian di tan khac nhau.
