Specification: Item: Single Door Hardware KitMaterial: Metal&SteelAdjustable Screw: The roller screws can be adjusted freely in any size within the door thickness from 1 1/4"-1 7/8".Maximum Door weight: 220lb for each doorThe top of the Doors to the ceiling : Min distance is 6.7" Exclusive Upgrade Design:Wide Applicability: Suitable for indoor decoration in kitchen, bedroom, dressing room, laundry room, Utility room, Entertainment console, club, pub and so on. Q&A: 1.Can the rail be cut down in size ?Yes, it can. But we have many sizes can be spliced. For convenience if you need the size specially,please contact with us.2.How to Choose Rail Size?Single Door Rail Length= 2 x Single Door Panel Width.(If your door width is 2FT, You will need 4FT Kit for single door)3.What if my studs don't line up with the pre-drilled holes in the rail? Attach a header board into your studs first, and then the rail can attach anywhere into the header board.