DIYHD White Bifold Sliding Barn Door Rolling Hardware, Front Mount Kit for 2 Doors / 4 Doors, (No Door). Hardware only, Not includes door panel. Max capacity 198lbs;Track pre-drilled 16″ apart holes, fit US standard 16″ apart studs walls. The height from top of the door to the top of the roller is 5 7/8. The gap between door and wall:Door closed:1″1 3/16″;Door opened:1/4″3/8″. DO NOT mount rail onto drywall directly, make sure the screws can be fixed on studs/solid wall. Fit door leaf Width 18″(total 36″). Fit door leaf Width 20″(total 40″). Fit door leaf Width 12″(total 48″). Track length 65″(32-1/2″). Fit door leaf Width 16″(total 64″). Fit door leaf Width 18″(total 72″). Fit door leaf Width 20″(total 80″). Full set hardware includes. Track X1+Track&wall connector X1 set. Bifold rollerX2 + Fixed roller lock bracketX2. 3 Surface for selection.