PRODUCT DESCRIPTION National Hardware 391S Folding Door Hardware Set is a complete hardware set for bi-fold doors. Allows full access to closets. Surface mount, no mortising required. Four-way adjustability for smooth operation. Easy installation. Size: 36" Color: White Material: Steel Safe Working Load (SWL): 30 lbs. Complete hardware set for bi-fold doors Easy installation Allows full access to closets Surface mount, no mortising required Four-way adjustability for smooth operation Concealed hardware. FROM THE MANUFACTURER This set is designed for bi-fold doors form 7/8-Inch to 1-3/8-Inch thick and up to 30-Pound each.