Special mounting hardware to enhance your Signicade sign stand. These items are referred to as well-nuts. Sold in packs of 4
You can attach a sign to the sign stands with standard wood screws, but in time (and with several sign changes) the screw holes will get enlarged and will no longer hold a screw.
This hardware fixes that problem. You simply drill holes where needed to hold your sign. Slip the black piece through the hole (from the front side of the sign). Put your screw in from the front side and tighten the screw. This causes the insert to expand, like a molly in drywall, creating a permanent screw receptacle.