Designed For Small Indoor Spaces? 3.3FT=40″Track, Bi-fold door hardware kit will only take up little space in your room, suitable for door thickness: 1-3/8″ to 1-5/8″; door top edge and ceiling=5″; rail load capacity: 330LBS; gap between wall and door=2+(door thickness). High Quality Products? Bifold Barn Door Hardware Kit is made of solid steel, which is wear-resistant, rust-proof, and moisture-proof. It is our goal to continuously improve product? Improved And Load Bearing? Through continuous research and practice, we have improved the product accessories to increase the service life and better load-bearing effect of Bi-Folding Sliding Barn Door Hardware Kit.