The engineering that went into this along with the quality of the material is exceptional,  my highest rating. The reason for 4 stars instead of 5 is the installation instructions. In the first section it states to install the support bar at a height 372 inches, when in fact it should be 62 inches. My installer thought I ordered the wrong g door and wanted me send it back,  I worked through the error and it wentup fine. The adjustability of the  support bar anchors was amazing along door adjusting 
mechanism too. I'm so impressed.