太感谢了。我要的就是double steel,但是

gauge number is 27, not good. it is torsion. our door is 8x7. maybe I will try wayne dalton. there is a one rank higher grade for amarr, whose double steel's gauge number is 25 (i guess for outlayer) and 27 (for inside layer). the door is thicker as well. R value much higher. maybe i should get est for that one. thanks again!