Johnson Bi-Fold Door Hardware Set. 4 Door. Residential. For standard panel or opening widths. Smooth operating, non-binding top hung bi-fold hardware designed for use with solid core wood door panels. Automatic top of door spacing eliminates gaps. Steel track with positive pivot lock. Surface-mounted pivots and guides (no hole drilling). Four-way adjustable bottom pivot bracket, shock absorbing hinges self-locate and automatically align doors. Track can be cut down to accommodate narrower doors or openings.