L.E Johnson 100FD724 4-Panel Hardware Set 72" - 4 Door System HEAVY DUTY - Bi-fold closet door hardware kit for 1" to 1 3/4" thick doors. PATENTED DESIGN - Heavy-duty tricycle hangers distribute weight equally and support heavy solid core door panels. EASY TO INSTALL - 2-piece non-mortise hinge enables door panels to be installed or removed by simply lifting off. SOLID MATERIALS - Heavy gauge steel pivot components hold heavy doors securely in place. MADE IN USA - Manufactured in the United States.