6 Panel MDF Composite Double Bi-Fold Barn Doors with Sliding Hardware KitCALHOME Bi fold Barn Door with sliding hardware kit contains everything needed to transform any doorway from a traditional door into a convenient, space saving and stylish sliding bi fold door. BIFOLD doors are folding doors made up of two pieces of door leafs that can be folded when opened, maximizing the use of space. Compared to sliding doors and swing doors, bi fold doors can open up a wider space while saving 50% of floor space (swing space),