CCJH 12FT Bypass Sliding Barn Door Hardware Kit Double Track Low Ceiling Heavy Duty for Double Wooden Doors, Basic HangerCCJH Bypass Sliding Barn Door Hardware Kit Double Track Pre purchase Information Doors are not included, only the hardware kit is for sale. Q: What is the compatible door thickness? A: 1 3 16" 2"(3 5cm). Q: What is the minimum clearance required above door? A: At least 6". Q: How to choose size A: Track's length should be at least of total door width or the opening (you can use the track which is a little bit longer). For example, if you have two