Prime-Line Mill Silver Steel Bi-fold Door Wheel Guide 2 pc

This is a spring-loaded 3/4 in. diameter nylon roller guide in a steel nail down base. The base is 3/8 in. with two nail down tabs on either side. It mounts on the top edge of a bi-fold door that is 1 in. to 1-3/8 in. thick and can hold up to 30 lbs. maximum.