QUALITY IS 100% UNDER CONTROL. We picked the most premium carbon steel to make the hardware heavy-duty and sturdier than the competition. The black powdered coating makes the paint stays forever and will not be scratched off. The wheels of the roller are made of high-quality nylon which ensures minimal noise when it glides on the track. Weight up to 220 lbs. FULLY OPTIMIZED CONNECTING AND SPACING. I understand how frustrated it was when you opened the box and found out multiple smaller tracks that were hard to line up and connect. Even worse when the spacing was not exactly 16 inches. We ve got them all figured out! The spacing is now exactly 16 inches. Track 7.5ft and under is only one piece track. Track 8ft and above are connected by two tracks using a junction plate, thus, the spacing between the middle two holes may not be 16 inches. BARN DOOR HARDWARE INSTALLATION MADE EASY. You hate to see vague installation manual that is just one piece of paper with hard to read measurements, badly drawing pictures, and barely any word instructions? Fortunately, in our installation manual, you will see the step by step instructions with USA standard fractional inch measurements, self-explanatory pictures, and concise word instructions. You are going to have a pleasant time while installing a sliding door at your home. Not the case here! We provide track sizes from 4ft to 20ft at a reasonable price. We also improved our packaging to make sure you will get everything you need in a timely manner! No more hassle to go back and forth for the missing or replacement parts. YOU ARE FULLY COVERED BY OUR PROFESSIONAL CUSTOMER SERVICE TEAM. As a company in the US, our professional customer service team are here to ensure your satisfaction with our products and quick response to any questions. Package includes all the hardware kit you need to install a sliding barn door. The barn door hardware can be used both inside and outside. It is rustproof, waterproof, and fireproof. The standard door thickness for our hardware is from 1 3/8” to 1 3/4”. If your door thickness is not within that range, please go to our second tab called “Customization Services” for more detailed instructions on how to customize it. The spacing between each hole is American Standard 16”. Tracks 7.5ft and under are one single track instead of being connected by multiple shorter tracks. Tracks 8ft to 16ft will be connected by two tracks. Tracks 18ft and 20ft will be connected by three tracks. Therefore, the spacing between the holes in the connecting section may not be 16”. The minimum clearance (from top of the door to the ceiling) you need to install this barn door hardware is 5”.